diff --git a/app/src/main/java/io/legado/app/help/JsExtensions.kt b/app/src/main/java/io/legado/app/help/JsExtensions.kt
index 4e9bf6c41..6a0a87109 100644
--- a/app/src/main/java/io/legado/app/help/JsExtensions.kt
+++ b/app/src/main/java/io/legado/app/help/JsExtensions.kt
@@ -29,7 +29,7 @@ object JsExtensions {
         return EncoderUtils.base64Decoder(str)
     }
 
-    fun base64Encoder(str: String): ByteArray? {
+    fun base64Encoder(str: String): String? {
         return EncoderUtils.base64Encoder(str)
     }
 
diff --git a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
index 287774a77..501e00777 100644
--- a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
+++ b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
@@ -576,7 +576,7 @@ class AnalyzeRule(private var book: BaseBook? = null) {
         return EncoderUtils.base64Decoder(str)
     }
 
-    fun base64Encoder(str: String): ByteArray? {
+    fun base64Encoder(str: String): String? {
         return EncoderUtils.base64Encoder(str)
     }
 
diff --git a/app/src/main/java/io/legado/app/utils/EncoderUtils.kt b/app/src/main/java/io/legado/app/utils/EncoderUtils.kt
index 3798bfa9c..9e98b35db 100644
--- a/app/src/main/java/io/legado/app/utils/EncoderUtils.kt
+++ b/app/src/main/java/io/legado/app/utils/EncoderUtils.kt
@@ -33,7 +33,7 @@ object EncoderUtils {
         }
     }
 
-    fun base64Encoder(str: String): ByteArray? {
-        return Base64.encode(str.toByteArray(), Base64.DEFAULT)
+    fun base64Encoder(str: String): String? {
+        return Base64.encodeToString(str.toByteArray(), Base64.DEFAULT)
     }
 }
\ No newline at end of file