diff --git a/app/src/main/java/io/legado/app/constant/AppConst.kt b/app/src/main/java/io/legado/app/constant/AppConst.kt
index ba51ce764..5cbb5a48b 100644
--- a/app/src/main/java/io/legado/app/constant/AppConst.kt
+++ b/app/src/main/java/io/legado/app/constant/AppConst.kt
@@ -18,10 +18,6 @@ object AppConst {
 
     const val UA_NAME = "User-Agent"
 
-    val userAgent: String by lazy {
-        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36"
-    }
-
     val SCRIPT_ENGINE: ScriptEngine by lazy {
         ScriptEngineManager().getEngineByName("rhino")
     }
diff --git a/app/src/main/java/io/legado/app/constant/PreferKey.kt b/app/src/main/java/io/legado/app/constant/PreferKey.kt
index 548356466..22a96517a 100644
--- a/app/src/main/java/io/legado/app/constant/PreferKey.kt
+++ b/app/src/main/java/io/legado/app/constant/PreferKey.kt
@@ -3,6 +3,7 @@ package io.legado.app.constant
 object PreferKey {
     const val language = "language"
     const val themeMode = "themeMode"
+    const val userAgent = "userAgent"
     const val hideStatusBar = "hideStatusBar"
     const val clickActionTL = "clickActionTopLeft"
     const val clickActionTC = "clickActionTopCenter"
diff --git a/app/src/main/java/io/legado/app/data/entities/BookSource.kt b/app/src/main/java/io/legado/app/data/entities/BookSource.kt
index 29ffdcfd1..1169ba690 100644
--- a/app/src/main/java/io/legado/app/data/entities/BookSource.kt
+++ b/app/src/main/java/io/legado/app/data/entities/BookSource.kt
@@ -5,11 +5,14 @@ import android.text.TextUtils
 import androidx.room.*
 import io.legado.app.App
 import io.legado.app.constant.AppConst
-import io.legado.app.constant.AppConst.userAgent
 import io.legado.app.constant.BookType
 import io.legado.app.data.entities.rule.*
+import io.legado.app.help.AppConfig
 import io.legado.app.help.JsExtensions
-import io.legado.app.utils.*
+import io.legado.app.utils.ACache
+import io.legado.app.utils.GSON
+import io.legado.app.utils.fromJsonObject
+import io.legado.app.utils.splitNotBlank
 import kotlinx.android.parcel.Parcelize
 import javax.script.SimpleBindings
 
@@ -51,7 +54,7 @@ data class BookSource(
     
     @Throws(Exception::class)
     fun getHeaderMap() = (HashMap<String, String>().apply {
-        this[AppConst.UA_NAME] = App.INSTANCE.getPrefString("user_agent") ?: userAgent
+        this[AppConst.UA_NAME] = AppConfig.userAgent
         header?.let {
             GSON.fromJsonObject<Map<String, String>>(
                 when {
diff --git a/app/src/main/java/io/legado/app/data/entities/RssSource.kt b/app/src/main/java/io/legado/app/data/entities/RssSource.kt
index 90418f0c0..0b40b3f13 100644
--- a/app/src/main/java/io/legado/app/data/entities/RssSource.kt
+++ b/app/src/main/java/io/legado/app/data/entities/RssSource.kt
@@ -4,12 +4,11 @@ import android.os.Parcelable
 import androidx.room.Entity
 import androidx.room.Index
 import androidx.room.PrimaryKey
-import io.legado.app.App
 import io.legado.app.constant.AppConst
+import io.legado.app.help.AppConfig
 import io.legado.app.help.JsExtensions
 import io.legado.app.utils.GSON
 import io.legado.app.utils.fromJsonObject
-import io.legado.app.utils.getPrefString
 import kotlinx.android.parcel.Parcelize
 import java.util.*
 import javax.script.SimpleBindings
@@ -54,7 +53,7 @@ data class RssSource(
 
     @Throws(Exception::class)
     fun getHeaderMap() = HashMap<String, String>().apply {
-        this[AppConst.UA_NAME] = App.INSTANCE.getPrefString("user_agent") ?: AppConst.userAgent
+        this[AppConst.UA_NAME] = AppConfig.userAgent
         header?.let {
             GSON.fromJsonObject<Map<String, String>>(
                 when {
diff --git a/app/src/main/java/io/legado/app/help/AppConfig.kt b/app/src/main/java/io/legado/app/help/AppConfig.kt
index 3ff4035e6..bf15b1781 100644
--- a/app/src/main/java/io/legado/app/help/AppConfig.kt
+++ b/app/src/main/java/io/legado/app/help/AppConfig.kt
@@ -12,6 +12,7 @@ import io.legado.app.utils.*
 object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
     private val context get() = App.INSTANCE
     val isGooglePlay = context.channel == "google"
+    var userAgent: String = getPrefUserAgent()
     var replaceEnableDefault = context.getPrefBoolean(PreferKey.replaceEnableDefault, true)
     var isEInkMode = context.getPrefString(PreferKey.themeMode) == "3"
     var clickActionTL = context.getPrefInt(PreferKey.clickActionTL, 2)
@@ -26,39 +27,28 @@ object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
 
     override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences?, key: String?) {
         when (key) {
-            PreferKey.themeMode -> {
-                isEInkMode = context.getPrefString(PreferKey.themeMode) == "3"
-            }
-            PreferKey.clickActionTL -> {
-                clickActionTL = context.getPrefInt(PreferKey.clickActionTL, 2)
-            }
-            PreferKey.clickActionTC -> {
-                clickActionTC = context.getPrefInt(PreferKey.clickActionTC, 2)
-            }
-            PreferKey.clickActionTR -> {
-                clickActionTR = context.getPrefInt(PreferKey.clickActionTR, 2)
-            }
-            PreferKey.clickActionML -> {
-                clickActionML = context.getPrefInt(PreferKey.clickActionML, 2)
-            }
-            PreferKey.clickActionMC -> {
-                clickActionMC = context.getPrefInt(PreferKey.clickActionMC, 2)
-            }
-            PreferKey.clickActionMR -> {
-                clickActionMR = context.getPrefInt(PreferKey.clickActionMR, 2)
-            }
-            PreferKey.clickActionBL -> {
-                clickActionBL = context.getPrefInt(PreferKey.clickActionBL, 2)
-            }
-            PreferKey.clickActionBC -> {
-                clickActionBC = context.getPrefInt(PreferKey.clickActionBC, 2)
-            }
-            PreferKey.clickActionBR -> {
-                clickActionBR = context.getPrefInt(PreferKey.clickActionBR, 2)
-            }
-            PreferKey.readBodyToLh -> {
-                ReadBookConfig.readBodyToLh = context.getPrefBoolean(PreferKey.readBodyToLh, true)
-            }
+            PreferKey.themeMode -> isEInkMode = context.getPrefString(PreferKey.themeMode) == "3"
+            PreferKey.clickActionTL -> clickActionTL =
+                context.getPrefInt(PreferKey.clickActionTL, 2)
+            PreferKey.clickActionTC -> clickActionTC =
+                context.getPrefInt(PreferKey.clickActionTC, 2)
+            PreferKey.clickActionTR -> clickActionTR =
+                context.getPrefInt(PreferKey.clickActionTR, 2)
+            PreferKey.clickActionML -> clickActionML =
+                context.getPrefInt(PreferKey.clickActionML, 2)
+            PreferKey.clickActionMC -> clickActionMC =
+                context.getPrefInt(PreferKey.clickActionMC, 2)
+            PreferKey.clickActionMR -> clickActionMR =
+                context.getPrefInt(PreferKey.clickActionMR, 2)
+            PreferKey.clickActionBL -> clickActionBL =
+                context.getPrefInt(PreferKey.clickActionBL, 2)
+            PreferKey.clickActionBC -> clickActionBC =
+                context.getPrefInt(PreferKey.clickActionBC, 2)
+            PreferKey.clickActionBR -> clickActionBR =
+                context.getPrefInt(PreferKey.clickActionBR, 2)
+            PreferKey.readBodyToLh -> ReadBookConfig.readBodyToLh =
+                context.getPrefBoolean(PreferKey.readBodyToLh, true)
+            PreferKey.userAgent -> userAgent = getPrefUserAgent()
         }
     }
 
@@ -157,5 +147,12 @@ object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
 
     val importKeepName get() = context.getPrefBoolean(PreferKey.importKeepName)
 
+    private fun getPrefUserAgent(): String {
+        val ua = context.getPrefString(PreferKey.userAgent)
+        if (ua.isNullOrBlank()) {
+            return "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36"
+        }
+        return ua
+    }
 }
 
diff --git a/app/src/main/java/io/legado/app/help/http/HttpHelper.kt b/app/src/main/java/io/legado/app/help/http/HttpHelper.kt
index a226b46d6..c6568f50e 100644
--- a/app/src/main/java/io/legado/app/help/http/HttpHelper.kt
+++ b/app/src/main/java/io/legado/app/help/http/HttpHelper.kt
@@ -1,6 +1,7 @@
 package io.legado.app.help.http
 
 import io.legado.app.constant.AppConst
+import io.legado.app.help.AppConfig
 import io.legado.app.help.http.api.HttpGetApi
 import io.legado.app.utils.NetworkUtils
 import kotlinx.coroutines.suspendCancellableCoroutine
@@ -41,7 +42,7 @@ object HttpHelper {
     fun simpleGet(url: String, encode: String? = null): String? {
         NetworkUtils.getBaseUrl(url)?.let { baseUrl ->
             val response = getApiService<HttpGetApi>(baseUrl, encode)
-                .get(url, mapOf(Pair(AppConst.UA_NAME, AppConst.userAgent)))
+                .get(url, mapOf(Pair(AppConst.UA_NAME, AppConfig.userAgent)))
                 .execute()
             return response.body()
         }
@@ -51,7 +52,7 @@ object HttpHelper {
     suspend fun simpleGetAsync(url: String, encode: String? = null): String? {
         NetworkUtils.getBaseUrl(url)?.let { baseUrl ->
             val response = getApiService<HttpGetApi>(baseUrl, encode)
-                .getAsync(url, mapOf(Pair(AppConst.UA_NAME, AppConst.userAgent)))
+                .getAsync(url, mapOf(Pair(AppConst.UA_NAME, AppConfig.userAgent)))
             return response.body()
         }
         return null
@@ -61,7 +62,7 @@ object HttpHelper {
         NetworkUtils.getBaseUrl(url)?.let { baseUrl ->
             return getByteRetrofit(baseUrl)
                 .create(HttpGetApi::class.java)
-                .getMapByteAsync(url, mapOf(), mapOf(Pair(AppConst.UA_NAME, AppConst.userAgent)))
+                .getMapByteAsync(url, mapOf(), mapOf(Pair(AppConst.UA_NAME, AppConfig.userAgent)))
                 .body()
         }
         return null
diff --git a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeUrl.kt b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeUrl.kt
index 16d9f3d29..aa4e7ec17 100644
--- a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeUrl.kt
+++ b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeUrl.kt
@@ -7,11 +7,11 @@ import com.bumptech.glide.load.model.GlideUrl
 import com.bumptech.glide.load.model.LazyHeaders
 import io.legado.app.constant.AppConst.SCRIPT_ENGINE
 import io.legado.app.constant.AppConst.UA_NAME
-import io.legado.app.constant.AppConst.userAgent
 import io.legado.app.constant.AppPattern.EXP_PATTERN
 import io.legado.app.constant.AppPattern.JS_PATTERN
 import io.legado.app.data.entities.BaseBook
 import io.legado.app.data.entities.BookChapter
+import io.legado.app.help.AppConfig
 import io.legado.app.help.JsExtensions
 import io.legado.app.help.http.*
 import io.legado.app.help.http.api.HttpGetApi
@@ -204,7 +204,7 @@ class AnalyzeUrl(
             }
         }
         headerMap[UA_NAME] ?: let {
-            headerMap[UA_NAME] = userAgent
+            headerMap[UA_NAME] = AppConfig.userAgent
         }
         when (method) {
             RequestMethod.GET -> {
diff --git a/app/src/main/java/io/legado/app/ui/config/OtherConfigFragment.kt b/app/src/main/java/io/legado/app/ui/config/OtherConfigFragment.kt
index e3a6d7e9f..eba591739 100644
--- a/app/src/main/java/io/legado/app/ui/config/OtherConfigFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/config/OtherConfigFragment.kt
@@ -1,5 +1,6 @@
 package io.legado.app.ui.config
 
+import android.annotation.SuppressLint
 import android.app.Activity.RESULT_OK
 import android.content.ComponentName
 import android.content.Intent
@@ -29,7 +30,9 @@ import io.legado.app.service.WebService
 import io.legado.app.ui.main.MainActivity
 import io.legado.app.ui.widget.image.CoverImageView
 import io.legado.app.ui.widget.number.NumberPickerDialog
+import io.legado.app.ui.widget.text.AutoCompleteTextView
 import io.legado.app.utils.*
+import kotlinx.android.synthetic.main.dialog_edit_text.view.*
 import java.io.File
 
 
@@ -48,6 +51,7 @@ class OtherConfigFragment : BasePreferenceFragment(),
     override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
         putPrefBoolean(PreferKey.processText, isProcessTextEnabled())
         addPreferencesFromResource(R.xml.pref_config_other)
+        upPreferenceSummary(PreferKey.userAgent, AppConfig.userAgent)
         upPreferenceSummary(PreferKey.threadCount, AppConfig.threadCount.toString())
         upPreferenceSummary(PreferKey.webPort, webPort.toString())
         upPreferenceSummary(PreferKey.defaultCover, getPrefString(PreferKey.defaultCover))
@@ -66,6 +70,7 @@ class OtherConfigFragment : BasePreferenceFragment(),
 
     override fun onPreferenceTreeClick(preference: Preference?): Boolean {
         when (preference?.key) {
+            PreferKey.userAgent -> showUserAgentDialog()
             PreferKey.threadCount -> NumberPickerDialog(requireContext())
                 .setTitle(getString(R.string.threads_num_title))
                 .setMaxValue(999)
@@ -117,8 +122,7 @@ class OtherConfigFragment : BasePreferenceFragment(),
             }
             PreferKey.showRss -> postEvent(EventBus.SHOW_RSS, "")
             PreferKey.defaultCover -> upPreferenceSummary(
-                key,
-                getPrefString(PreferKey.defaultCover)
+                key, getPrefString(PreferKey.defaultCover)
             )
             PreferKey.language -> listView.postDelayed({
                 LanguageUtils.setConfiguration(App.INSTANCE)
@@ -127,6 +131,9 @@ class OtherConfigFragment : BasePreferenceFragment(),
                 App.INSTANCE.startActivity(intent)
                 Process.killProcess(Process.myPid())
             }, 1000)
+            PreferKey.userAgent -> listView.post {
+                upPreferenceSummary(PreferKey.userAgent, AppConfig.userAgent)
+            }
         }
     }
 
@@ -145,6 +152,28 @@ class OtherConfigFragment : BasePreferenceFragment(),
         }
     }
 
+    @SuppressLint("InflateParams")
+    private fun showUserAgentDialog() {
+        alert("UserAgent") {
+            var editText: AutoCompleteTextView? = null
+            customView {
+                layoutInflater.inflate(R.layout.dialog_edit_text, null).apply {
+                    edit_view.setText(AppConfig.userAgent)
+                    editText = edit_view
+                }
+            }
+            okButton {
+                val userAgent = editText?.text?.toString()
+                if (userAgent.isNullOrBlank()) {
+                    removePref(PreferKey.userAgent)
+                } else {
+                    putPrefString(PreferKey.userAgent, userAgent)
+                }
+            }
+            noButton()
+        }.show()
+    }
+
     private fun clearCache() {
         requireContext().alert(
             titleResource = R.string.clear_cache,
diff --git a/app/src/main/res/values/pref_key_value.xml b/app/src/main/res/values/pref_key_value.xml
index a0247482b..266c4cb51 100644
--- a/app/src/main/res/values/pref_key_value.xml
+++ b/app/src/main/res/values/pref_key_value.xml
@@ -2,15 +2,8 @@
 <resources>
     <string name="pk_auto_refresh" translatable="false">auto_refresh</string>
     <string name="pk_requested_direction" translatable="false">list_screen_direction</string>
-    <string name="pk_full_screen" translatable="false">full_screen</string>
-    <string name="pk_threads_num" translatable="false">threads_num</string>
-    <string name="pk_user_agent" translatable="false">user_agent</string>
     <string name="pk_bookshelf_px" translatable="false">bookshelf_px</string>
-    <string name="pk_read_type" translatable="false">read_type</string>
-    <string name="pk_find_expand_group" translatable="false">expandGroupFind</string>
     <string name="pk_default_read" translatable="false">defaultToRead</string>
-    <string name="pk_auto_download" translatable="false">autoDownload</string>
-    <string name="pk_check_update" translatable="false">checkUpdate</string>
     <string name="legado_gzh" translatable="false">开源阅读</string>
 
     <string name="source_rule_url" translatable="false">https://alanskycn.gitee.io/teachme/</string>
diff --git a/app/src/main/res/xml/pref_config_other.xml b/app/src/main/res/xml/pref_config_other.xml
index 1a1541988..7077d665b 100644
--- a/app/src/main/res/xml/pref_config_other.xml
+++ b/app/src/main/res/xml/pref_config_other.xml
@@ -51,6 +51,10 @@
         app:iconSpaceReserved="false"
         app:layout="@layout/view_preference_category">
 
+        <io.legado.app.ui.widget.prefs.Preference
+            android:key="userAgent"
+            android:title="UserAgent" />
+
         <io.legado.app.ui.widget.prefs.SwitchPreference
             android:defaultValue="true"
             android:key="replaceEnableDefault"