diff --git a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/DefaultDeployer.kt b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/DefaultDeployer.kt
index e6c9cc2..95f8122 100644
--- a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/DefaultDeployer.kt
+++ b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/DefaultDeployer.kt
@@ -106,7 +106,9 @@ internal object DefaultDeployer {
         val properties = mutableMapOf<String, PropertyTypeValue>()
         val resolveProperties = mutableMapOf<Any?, Any?>()
 
-        config.permanentKeyValues.forEach { (key, value) -> properties[key] = value.createTypeValueByType(config.useTypeAutoConversion) }
+        config.permanentKeyValues.forEach { (key, value) ->
+            properties[key] = value.createTypeValueByType(config.useTypeAutoConversion, key)
+        }
         config.locations.forEach { location ->
             when (location) {
                 GropifyLocation.CurrentProject -> createProperties(config, descriptor.currentDir).forEach { resolveProperties.putAll(it) }
@@ -136,7 +138,7 @@ internal object DefaultDeployer {
                 }
             } ?: true
         }.toMutableMap().also { resolveKeyValues ->
-            resolveKeyValues.onEach { (key, value) ->
+            resolveKeyValues.forEach { (key, value) ->
                 val resolveKeys = mutableListOf<String>()
 
                 fun String.resolveValue(): String = replaceInterpolation { matchKey ->
@@ -155,17 +157,25 @@ internal object DefaultDeployer {
                 }
 
                 if (value.hasInterpolation()) resolveKeyValues[key] = value.resolveValue()
-            }.takeIf { config.keyValuesRules.isNotEmpty() }?.forEach { (key, value) ->
-                config.keyValuesRules[key]?.also { resolveKeyValues[key] = it(value) }
             }
 
             properties.putAll(resolveKeyValues.map { (key, value) ->
-                key to value.createTypeValue(config.useTypeAutoConversion)
+                key to value.createTypeValue(config.useTypeAutoConversion, key)
             })
         }
 
         // Replace all key-values if exists.
-        config.replacementKeyValues.forEach { (key, value) -> properties[key] = value.createTypeValueByType(config.useTypeAutoConversion) }
+        config.replacementKeyValues.forEach { (key, value) ->
+            properties[key] = value.createTypeValueByType(config.useTypeAutoConversion, key)
+        }
+
+        // Apply key-values rules.
+        properties.forEach { (key, value) ->
+            val (mapper, type) = config.keyValuesRules[key] ?: return@forEach
+
+            val resolveValue = mapper(value.raw).createTypeValue(config.useTypeAutoConversion, key, type)
+            properties[key] = resolveValue
+        }
 
         return properties
     }
diff --git a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/extension/dsl/configure/GropifyConfigureExtension.kt b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/extension/dsl/configure/GropifyConfigureExtension.kt
index de7c177..ef585ab 100644
--- a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/extension/dsl/configure/GropifyConfigureExtension.kt
+++ b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/extension/dsl/configure/GropifyConfigureExtension.kt
@@ -30,11 +30,13 @@ import com.highcapable.gropify.plugin.Gropify
 import com.highcapable.gropify.plugin.config.extension.create
 import com.highcapable.gropify.plugin.config.proxy.GropifyConfig
 import com.highcapable.gropify.plugin.config.type.GropifyLocation
+import com.highcapable.gropify.plugin.generator.extension.PropertyValueMapper
 import com.highcapable.gropify.plugin.generator.extension.PropertyValueRule
 import com.highcapable.gropify.utils.KeywordsDetector
 import com.highcapable.gropify.utils.extension.isStartsWithLetter
 import org.gradle.api.Action
 import org.gradle.api.initialization.Settings
+import kotlin.reflect.KClass
 
 /**
  * Configure extension for Gropify.
@@ -447,8 +449,13 @@ open class GropifyConfigureExtension internal constructor() {
          *
          * ```kotlin
          * keyValuesRules(
-         *     "some.key1" to createValueRule { if (it.contains("_")) it.replace("_", "-") else it },
-         *     "some.key2" to createValueRule { "$it-value" }
+         *     "some.key1" to ValueRule { if (it.contains("_")) it.replace("_", "-") else it },
+         *     "some.key2" to ValueRule { "$it-value" },
+         *     // You can also specify the expected type class,
+         *     // the type you specify will be used during generation,
+         *     // and an exception will be thrown if the type cannot be converted correctly.
+         *     // If the [useTypeAutoConversion] is not enabled, this parameter will be ignored.
+         *     "some.key3" to ValueRule(Int::class)
          * )
          * ```
          *
@@ -483,10 +490,13 @@ open class GropifyConfigureExtension internal constructor() {
 
         /**
          * Create a new properties' values rule.
+         * @param type specify the expected type class, or null to auto-detect,
+         * if the [useTypeAutoConversion] is not enabled, this parameter will be ignored.
          * @param rule callback current rule.
          * @return [PropertyValueRule]
          */
-        fun ValueRule(rule: PropertyValueRule) = rule
+        @JvmOverloads
+        fun ValueRule(type: KClass<*>? = null, rule: PropertyValueMapper = { it }) = rule to type
 
         /**
          * Set where to find properties' key-values.
diff --git a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/Generator.kt b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/Generator.kt
index 685fff3..8d4a3b4 100644
--- a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/Generator.kt
+++ b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/Generator.kt
@@ -22,10 +22,12 @@
 package com.highcapable.gropify.plugin.generator.extension
 
 import com.highcapable.gropify.utils.extension.underscore
+import kotlin.reflect.KClass
 
 internal typealias PropertyMap = MutableMap<String, PropertyTypeValue>
 internal typealias PropertyOptimizeMap = MutableMap<String, Pair<String, PropertyTypeValue>>
-internal typealias PropertyValueRule = (value: String) -> String
+internal typealias PropertyValueMapper = (value: String) -> String
+internal typealias PropertyValueRule = Pair<PropertyValueMapper, KClass<*>?>
 
 /**
  * Optimize property keys for code generation.
diff --git a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/PropertyType.kt b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/PropertyType.kt
index d82553b..1c818fc 100644
--- a/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/PropertyType.kt
+++ b/gropify-gradle-plugin/src/main/kotlin/com/highcapable/gropify/plugin/generator/extension/PropertyType.kt
@@ -22,6 +22,7 @@
 package com.highcapable.gropify.plugin.generator.extension
 
 import com.highcapable.gropify.internal.error
+import com.highcapable.gropify.internal.require
 import com.highcapable.gropify.plugin.Gropify
 import com.highcapable.gropify.utils.extension.isNumeric
 import kotlin.reflect.KClass
@@ -30,9 +31,12 @@ import kotlin.reflect.KClass
  * Create [PropertyTypeValue] from [String] value.
  * @receiver [String]
  * @param autoConversion whether to enable auto conversion.
+ * @param key the property key name.
+ * @param type specify the expected type class, or null to auto-detect,
+ * if the [autoConversion] is not `true`, this parameter will be ignored.
  * @return [PropertyTypeValue]
  */
-internal fun String.createTypeValue(autoConversion: Boolean): PropertyTypeValue {
+internal fun String.createTypeValue(autoConversion: Boolean, key: String, type: KClass<*>? = null): PropertyTypeValue {
     var isStringType = false
     val valueString = replace("\n", "\\n")
         .replace("\r", "\\r")
@@ -47,6 +51,56 @@ internal fun String.createTypeValue(autoConversion: Boolean): PropertyTypeValue
     if (!autoConversion) return PropertyTypeValue(this, "\"$valueString\"", String::class)
 
     val trimmed = valueString.trim()
+
+    if (type != null) {
+        val finalValue = when (type) {
+            String::class -> "\"$valueString\""
+            CharSequence::class -> "\"$valueString\""
+            Char::class -> trimmed.firstOrNull()?.let { "'$it'" }
+                ?: Gropify.error("The \"$key\" value is empty and cannot be converted to Char type.")
+            Boolean::class -> if (trimmed.toBooleanStrictOrNull() != null)
+                trimmed
+            else ((trimmed.toIntOrNull() ?: 0) > 0).toString()
+            Int::class -> {
+                val intValue = trimmed.toIntOrNull()
+                Gropify.require(intValue != null && intValue in Int.MIN_VALUE..Int.MAX_VALUE) {
+                    "The \"$key\" value \"$this\" cannot be converted to Int type."
+                }
+
+                trimmed
+            }
+            Long::class -> {
+                Gropify.require(trimmed.toLongOrNull() != null) {
+                    "The \"$key\" value \"$this\" cannot be converted to Long type."
+                }
+
+                if (trimmed.endsWith("L")) trimmed else "${trimmed}L"
+            }
+            Double::class -> {
+                val doubleValue = trimmed.toDoubleOrNull()
+                Gropify.require(doubleValue != null && !doubleValue.isInfinite()) {
+                    "The \"$key\" value \"$this\" cannot be converted to Double type."
+                }
+                    
+                trimmed
+            }
+            Float::class -> {
+                val floatValue = trimmed.toFloatOrNull()
+                Gropify.require(floatValue != null && !floatValue.isInfinite()) {
+                    "The \"$key\" value \"$this\" cannot be converted to Float type."
+                }
+                    
+                if (trimmed.endsWith("f") || trimmed.endsWith("F")) trimmed else "${trimmed}f"
+            }
+            else -> Gropify.error(
+                "Unsupported property \"$key\" value type: ${type.qualifiedName}, " +
+                    "only String, CharSequence, Char, Boolean, Int, Long, Float, Double are supported."
+            )
+        }
+
+        return PropertyTypeValue(this, finalValue, type)
+    }
+
     val typeSpec = when {
         isStringType -> String::class
         trimmed.toBooleanStrictOrNull() != null -> Boolean::class
@@ -79,9 +133,10 @@ internal fun String.createTypeValue(autoConversion: Boolean): PropertyTypeValue
  * Create [PropertyTypeValue] from [Any] value's type.
  * @receiver [Any]
  * @param autoConversion whether to enable auto conversion.
+ * @param key the property key name.
  * @return [PropertyTypeValue]
  */
-internal fun Any.createTypeValueByType(autoConversion: Boolean): PropertyTypeValue {
+internal fun Any.createTypeValueByType(autoConversion: Boolean, key: String): PropertyTypeValue {
     val typeSpec = this.javaClass.kotlin
     val valueString = toString()
         .replace("\n", "\\n")
@@ -94,12 +149,13 @@ internal fun Any.createTypeValueByType(autoConversion: Boolean): PropertyTypeVal
     val finalValue = if (autoConversion) when (typeSpec) {
         String::class, CharSequence::class -> "\"$trimmed\""
         Char::class -> "'$trimmed'"
+        Boolean::class -> trimmed
         Long::class -> if (trimmed.endsWith("L")) trimmed else "${trimmed}L"
         Float::class -> if (trimmed.endsWith("f") || trimmed.endsWith("F")) trimmed else "${trimmed}f"
         Int::class, Double::class -> trimmed
         else -> Gropify.error(
-            "Unsupported property value type: ${typeSpec.qualifiedName}, " +
-                "only String, CharSequence, Char, Int, Long, Float, Double are supported."
+            "Unsupported property \"$key\" value type: ${typeSpec.qualifiedName}, " +
+                "only String, CharSequence, Char, Boolean, Int, Long, Float, Double are supported."
         )
     } else "\"$valueString\""