diff --git a/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.cpp b/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.cpp
index ce678319e71..74f09cb3257 100644
--- a/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.cpp
+++ b/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.cpp
@@ -9,7 +9,9 @@
 
 
 void kotlin::gc::FinalizerProcessor::StartFinalizerThreadIfNone() noexcept {
+    std::unique_lock guard(threadCreatingMutex_);
     if (finalizerThread_.joinable()) return;
+
     finalizerThread_ = ScopedThread(ScopedThread::attributes().name("GC finalizer processor"), [this] {
         Kotlin_initRuntimeIfNeeded();
         {
diff --git a/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.hpp b/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.hpp
index 85cfca0e89c..f20acfc1b59 100644
--- a/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.hpp
+++ b/kotlin-native/runtime/src/gc/cms/cpp/FinalizerProcessor.hpp
@@ -38,6 +38,8 @@ private:
     std::mutex initializedMutex_;
     std::condition_variable initializedCondVar_;
     bool initialized_ = false;
+
+    std::mutex threadCreatingMutex_;
 };
 
 } // namespace kotlin::gc