diff --git a/CHANGELOG.md b/CHANGELOG.md
index 42ce1b7..72cb85c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 * Add ClassMetadata.kind
 * Add ConstructorMetadata.isPrimary
 * Add DeclarationMetadata.visibility
+* Add ParameterMetadata.hasDefaultValue
 * Update to Kotlin 1.2.0
 
 ## 1.0.0 (Feb 15, 2016)
diff --git a/src/main/java/kotlinx/reflect/lite/ParameterMetadata.kt b/src/main/java/kotlinx/reflect/lite/ParameterMetadata.kt
index 5b18199..14413fe 100644
--- a/src/main/java/kotlinx/reflect/lite/ParameterMetadata.kt
+++ b/src/main/java/kotlinx/reflect/lite/ParameterMetadata.kt
@@ -29,4 +29,11 @@ interface ParameterMetadata {
      * Metadata for the type of this parameter.
      */
     val type: TypeMetadata
+
+    /**
+     * `true` if this parameter declares a default value in the source code.
+     *
+     * Note that in case the parameter inherits a default value from a super function, it's not considered to be declaring a default value.
+     */
+    val hasDefaultValue: Boolean
 }
diff --git a/src/main/java/kotlinx/reflect/lite/impl/ParameterMetadataImpl.kt b/src/main/java/kotlinx/reflect/lite/impl/ParameterMetadataImpl.kt
index 3fc1956..d1fd458 100644
--- a/src/main/java/kotlinx/reflect/lite/impl/ParameterMetadataImpl.kt
+++ b/src/main/java/kotlinx/reflect/lite/impl/ParameterMetadataImpl.kt
@@ -18,6 +18,7 @@ package kotlinx.reflect.lite.impl
 
 import kotlinx.reflect.lite.ParameterMetadata
 import kotlinx.reflect.lite.TypeMetadata
+import org.jetbrains.kotlin.serialization.Flags
 import org.jetbrains.kotlin.serialization.ProtoBuf
 import org.jetbrains.kotlin.serialization.deserialization.NameResolver
 
@@ -30,4 +31,7 @@ internal class ParameterMetadataImpl(
 
     override val type: TypeMetadata
         get() = TypeMetadataImpl(proto.type, nameResolver)
+
+    override val hasDefaultValue: Boolean
+        get() = Flags.DECLARES_DEFAULT_VALUE.get(proto.flags)
 }
diff --git a/src/test/java/kotlinx/reflect/lite/test/SmokeTest.kt b/src/test/java/kotlinx/reflect/lite/test/SmokeTest.kt
index 6dc2b51..e69c4be 100644
--- a/src/test/java/kotlinx/reflect/lite/test/SmokeTest.kt
+++ b/src/test/java/kotlinx/reflect/lite/test/SmokeTest.kt
@@ -182,4 +182,18 @@ class SmokeTest {
         assertFalse(classMetadata.getProperty(klass.fieldByName("const"))!!.isLateinit)
         assertFalse(classMetadata.getProperty(klass.fieldByName("lateinit"))!!.isConst)
     }
+
+    @Test
+    fun testParameterDefaultValue() {
+        val klass = ParameterDefaultValue::class.java
+        val subclass = ParameterDefaultValueSubclass::class.java
+
+        val parameters = ReflectionLite.loadClassMetadata(klass)!!.getFunction(klass.methodByName("foo"))!!.parameters
+        assertFalse(parameters[0].hasDefaultValue)
+        assertTrue(parameters[1].hasDefaultValue)
+
+        val subclassParameters = ReflectionLite.loadClassMetadata(subclass)!!.getFunction(subclass.methodByName("foo"))!!.parameters
+        assertFalse(subclassParameters[0].hasDefaultValue)
+        assertFalse(subclassParameters[1].hasDefaultValue)
+    }
 }
diff --git a/src/test/java/kotlinx/reflect/lite/test/testData.kt b/src/test/java/kotlinx/reflect/lite/test/testData.kt
index 0541cbb..7df7d58 100644
--- a/src/test/java/kotlinx/reflect/lite/test/testData.kt
+++ b/src/test/java/kotlinx/reflect/lite/test/testData.kt
@@ -106,3 +106,11 @@ object CallableModifiers {
     lateinit var lateinit: String
     const val const = 42
 }
+
+open class ParameterDefaultValue {
+    open fun foo(x: Int, y: Int? = null) {}
+}
+
+class ParameterDefaultValueSubclass : ParameterDefaultValue() {
+    override fun foo(x: Int, y: Int?) {}
+}