diff --git a/app/src/main/java/io/legado/app/data/entities/BaseBook.kt b/app/src/main/java/io/legado/app/data/entities/BaseBook.kt
index acf795430..0c96c2123 100644
--- a/app/src/main/java/io/legado/app/data/entities/BaseBook.kt
+++ b/app/src/main/java/io/legado/app/data/entities/BaseBook.kt
@@ -3,7 +3,7 @@ package io.legado.app.data.entities
 import io.legado.app.utils.splitNotBlank
 
 interface BaseBook {
-    var variableMap: HashMap<String, String>
+    var variableMap: HashMap<String, String>?
     var kind: String?
     var wordCount: String?
 
diff --git a/app/src/main/java/io/legado/app/data/entities/Book.kt b/app/src/main/java/io/legado/app/data/entities/Book.kt
index f04686bd8..d98f79603 100644
--- a/app/src/main/java/io/legado/app/data/entities/Book.kt
+++ b/app/src/main/java/io/legado/app/data/entities/Book.kt
@@ -47,9 +47,16 @@ data class Book(
     var useReplaceRule: Boolean = true,         // 正文使用净化替换规则
     var variable: String? = null                // 自定义书籍变量信息(用于书源规则检索书籍信息)
 ) : Parcelable, BaseBook {
+
     @Ignore
     @IgnoredOnParcel
-    override var variableMap: HashMap<String, String> = GSON.fromJsonObject(variable) ?: HashMap()
+    override var variableMap: HashMap<String, String>? = null
+        get() {
+            if (field == null) {
+                field = GSON.fromJsonObject<HashMap<String, String>>(variable) ?: HashMap()
+            }
+            return field
+        }
 
     @Ignore
     @IgnoredOnParcel
@@ -66,7 +73,7 @@ data class Book(
     fun getDisplayIntro() = if (customIntro.isNullOrEmpty()) intro else customIntro
 
     override fun putVariable(key: String, value: String) {
-        variableMap[key] = value
+        variableMap?.put(key, value)
         variable = GSON.toJson(variableMap)
     }
 
diff --git a/app/src/main/java/io/legado/app/data/entities/BookChapter.kt b/app/src/main/java/io/legado/app/data/entities/BookChapter.kt
index 61006a6ea..b88151e5d 100644
--- a/app/src/main/java/io/legado/app/data/entities/BookChapter.kt
+++ b/app/src/main/java/io/legado/app/data/entities/BookChapter.kt
@@ -3,7 +3,11 @@ package io.legado.app.data.entities
 import android.os.Parcelable
 import androidx.room.Entity
 import androidx.room.ForeignKey
+import androidx.room.Ignore
 import androidx.room.Index
+import io.legado.app.utils.GSON
+import io.legado.app.utils.fromJsonObject
+import kotlinx.android.parcel.IgnoredOnParcel
 import kotlinx.android.parcel.Parcelize
 
 
@@ -11,7 +15,10 @@ import kotlinx.android.parcel.Parcelize
 @Entity(
     tableName = "chapters",
     primaryKeys = ["url", "bookUrl"],
-    indices = [(Index(value = ["bookUrl"], unique = false)), (Index(value = ["bookUrl", "index"], unique = true))],
+    indices = [(Index(value = ["bookUrl"], unique = false)), (Index(
+        value = ["bookUrl", "index"],
+        unique = true
+    ))],
     foreignKeys = [(ForeignKey(
         entity = Book::class,
         parentColumns = ["bookUrl"],
@@ -27,6 +34,25 @@ data class BookChapter(
     var resourceUrl: String? = null,    // 音频真实URL
     var tag: String? = null,            //
     var start: Long? = null,            // 章节起始位置
-    var end: Long? = null               // 章节终止位置
-) : Parcelable
+    var end: Long? = null,               // 章节终止位置
+    var variable: String? = null
+) : Parcelable {
+
+    @Ignore
+    @IgnoredOnParcel
+    var variableMap: HashMap<String, String>? = null
+        private set
+        get() {
+            if (field == null) {
+                field = GSON.fromJsonObject<HashMap<String, String>>(variable) ?: HashMap()
+            }
+            return field
+        }
+
+    fun putVariable(key: String, value: String) {
+        variableMap?.put(key, value)
+        variable = GSON.toJson(variableMap)
+    }
+
+}
 
diff --git a/app/src/main/java/io/legado/app/data/entities/SearchBook.kt b/app/src/main/java/io/legado/app/data/entities/SearchBook.kt
index 5d3fd9e1f..acca6db8f 100644
--- a/app/src/main/java/io/legado/app/data/entities/SearchBook.kt
+++ b/app/src/main/java/io/legado/app/data/entities/SearchBook.kt
@@ -56,12 +56,18 @@ data class SearchBook(
         return other.originOrder - this.originOrder
     }
 
-    @IgnoredOnParcel
     @Ignore
-    override var variableMap: HashMap<String, String> = GSON.fromJsonObject(variable) ?: HashMap()
+    @IgnoredOnParcel
+    override var variableMap: HashMap<String, String>? = null
+        get() {
+            if (field == null) {
+                field = GSON.fromJsonObject<HashMap<String, String>>(variable) ?: HashMap()
+            }
+            return field
+        }
 
     override fun putVariable(key: String, value: String) {
-        variableMap[key] = value
+        variableMap?.put(key, value)
         variable = GSON.toJson(variableMap)
     }