diff --git a/plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/common/TypeUtil.kt b/plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/common/TypeUtil.kt
index 80eaf2f4afc..4535c4ce7c9 100644
--- a/plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/common/TypeUtil.kt
+++ b/plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/common/TypeUtil.kt
@@ -125,7 +125,7 @@ fun AbstractSerialGenerator.findTypeSerializerOrContextUnchecked(
     if (kType.isTypeParameter()) return null
     annotations.serializableWith(module)?.let { return it.toClassDescriptor }
     additionalSerializersInScopeOfCurrentFile[kType]?.let { return it }
-
+    if (kType.isMarkedNullable) return findTypeSerializerOrContextUnchecked(module, kType.makeNotNullable())
     if (kType in contextualKClassListInCurrentFile) return module.getClassFromSerializationPackage(SpecialBuiltins.contextSerializer)
     return analyzeSpecialSerializers(module, annotations) ?: findTypeSerializer(module, kType)
 }