diff --git a/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt b/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
index 65cd797a16a..47cf81629f3 100644
--- a/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
+++ b/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
@@ -350,6 +350,9 @@ class StubIrBuilder(private val context: StubIrContext) {
                 typealiases.toList(),
                 containers.toList()
         )
+
+        stubs.addExperimentalAnnotations()
+
         return StubIrBuilderResult(
                 stubs,
                 buildingContext.declarationMapper,
@@ -358,6 +361,50 @@ class StubIrBuilder(private val context: StubIrContext) {
         )
     }
 
+    private fun StubContainer.addExperimentalAnnotations() {
+        fun MutableList<AnnotationStub>.addExperimentalIfNecessary() {
+            if (!configuration.disableExperimentalAnnotation)
+                this.add(AnnotationStub.ExperimentalForeignApi)
+        }
+
+        this.accept(object : StubIrVisitor<Unit, Unit> {
+            override fun visitSimpleStubContainer(simpleStubContainer: SimpleStubContainer, data: Unit) {
+                simpleStubContainer.children.forEach { it.accept(this, data) }
+                simpleStubContainer.simpleContainers.forEach { visitSimpleStubContainer(it, data) }
+            }
+
+            override fun visitClass(element: ClassStub, data: Unit) {
+                val annotations = when (element) {
+                    is ClassStub.Companion -> return // Nested, see below.
+                    is ClassStub.Enum -> element.annotations
+                    is ClassStub.Simple -> element.annotations
+                }
+                annotations.addExperimentalIfNecessary()
+                // Not visiting nested declarations intentionally -- they inherit opt-in requirement from the enclosing
+                // class.
+            }
+
+            override fun visitTypealias(element: TypealiasStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            override fun visitFunction(element: FunctionStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            override fun visitProperty(element: PropertyStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            // Not visiting nested declarations intentionally -- they inherit opt-in requirement from the enclosing
+            // class.
+            override fun visitConstructor(constructorStub: ConstructorStub, data: Unit) {}
+
+            // Property accessors inherit opt-in requirements from the property.
+            override fun visitPropertyAccessor(propertyAccessor: PropertyAccessor, data: Unit) {}
+        }, Unit)
+    }
+
     private fun generateStubsForWrappedMacro(macro: WrappedMacroDef) {
         try {
             generateStubsForGlobal(GlobalDecl(macro.name, macro.type, isConst = true))