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 30f96e2b0..cc1a23bb6 100644
--- a/app/src/main/java/io/legado/app/constant/PreferKey.kt
+++ b/app/src/main/java/io/legado/app/constant/PreferKey.kt
@@ -80,6 +80,8 @@ object PreferKey {
     const val useZhLayout = "useZhLayout"
     const val fullScreenGesturesSupport = "fullScreenGesturesSupport"
     const val highBrush = "highBrush"
+    const val brightness = "brightness"
+    const val nightBrightness = "nightBrightness"
 
     const val cPrimary = "colorPrimary"
     const val cAccent = "colorAccent"
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 97a43f359..01b02eac5 100644
--- a/app/src/main/java/io/legado/app/help/AppConfig.kt
+++ b/app/src/main/java/io/legado/app/help/AppConfig.kt
@@ -79,6 +79,20 @@ object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
             appCtx.putPrefBoolean(PreferKey.showUnread, value)
         }
 
+    var readBrightness: Int
+        get() = if (isNightTheme) {
+            appCtx.getPrefInt(PreferKey.nightBrightness, 100)
+        } else {
+            appCtx.getPrefInt(PreferKey.brightness, 100)
+        }
+        set(value) {
+            if (isNightTheme) {
+                appCtx.putPrefInt(PreferKey.nightBrightness, value)
+            } else {
+                appCtx.putPrefInt(PreferKey.brightness, value)
+            }
+        }
+
     val useDefaultCover: Boolean
         get() = appCtx.getPrefBoolean(PreferKey.useDefaultCover, false)
 
@@ -232,7 +246,7 @@ object AppConfig : SharedPreferences.OnSharedPreferenceChangeListener {
         val ua = appCtx.getPrefString(PreferKey.userAgent)
         if (ua.isNullOrBlank()) {
             return "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36"
-    }
+        }
         return ua
     }
 }
diff --git a/app/src/main/java/io/legado/app/ui/book/read/ReadMenu.kt b/app/src/main/java/io/legado/app/ui/book/read/ReadMenu.kt
index 671b7ba5d..9b0cee69d 100644
--- a/app/src/main/java/io/legado/app/ui/book/read/ReadMenu.kt
+++ b/app/src/main/java/io/legado/app/ui/book/read/ReadMenu.kt
@@ -85,7 +85,7 @@ class ReadMenu @JvmOverloads constructor(
         vwBg.setOnClickListener(null)
         vwNavigationBar.setOnClickListener(null)
         llBrightness.setOnClickListener(null)
-        seekBrightness.progress = context.getPrefInt("brightness", 100)
+        seekBrightness.progress = AppConfig.readBrightness
     }
 
     fun upBrightnessState() {
@@ -96,7 +96,7 @@ class ReadMenu @JvmOverloads constructor(
             binding.ivBrightnessAuto.setColorFilter(context.buttonDisabledColor)
             binding.seekBrightness.isEnabled = true
         }
-        setScreenBrightness(context.getPrefInt("brightness", 100))
+        setScreenBrightness(AppConfig.readBrightness)
     }
 
     /**
@@ -156,7 +156,7 @@ class ReadMenu @JvmOverloads constructor(
             }
 
             override fun onStopTrackingTouch(seekBar: SeekBar) {
-                context.putPrefInt("brightness", seekBar.progress)
+                AppConfig.readBrightness = seekBar.progress
             }
 
         })