diff --git a/compiler/testData/diagnostics/testsWithJsStdLib/native/nativeSetter/onToplevelExtensionFun.kt b/compiler/testData/diagnostics/testsWithJsStdLib/native/nativeSetter/onToplevelExtensionFun.kt
index 6352c917d21..7b34c5b72c3 100644
--- a/compiler/testData/diagnostics/testsWithJsStdLib/native/nativeSetter/onToplevelExtensionFun.kt
+++ b/compiler/testData/diagnostics/testsWithJsStdLib/native/nativeSetter/onToplevelExtensionFun.kt
@@ -22,10 +22,10 @@ fun Int.set6(a: Double, v: String): <!NATIVE_SETTER_WRONG_RETURN_TYPE!>Number<!>
 fun Any.foo(<!NATIVE_INDEXER_CAN_NOT_HAVE_DEFAULT_ARGUMENTS!>a: String = "0.0"<!>, <!NATIVE_INDEXER_CAN_NOT_HAVE_DEFAULT_ARGUMENTS!>v: String = "str"<!>) = "OK"
 
 <!NATIVE_INDEXER_WRONG_PARAMETER_COUNT!>@nativeSetter
-fun Int.set(<!NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER!>a: <!UNRESOLVED_REFERENCE!>A<!><!>): Int?<!> = 1
+fun Int.set(a: <!UNRESOLVED_REFERENCE!>A<!>): Int?<!> = 1
 
 <!NATIVE_INDEXER_WRONG_PARAMETER_COUNT!>@nativeSetter
 fun Int.set2(): String?<!> = "OK"
 
 <!NATIVE_INDEXER_WRONG_PARAMETER_COUNT!>@nativeSetter
-fun Int.set3(<!NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER!>a: Any<!>, b: Int, c: Any?)<!> {}
\ No newline at end of file
+fun Int.set3(<!NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER!>a: Any<!>, b: Int, c: Any?)<!> {}
diff --git a/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt b/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
index aad1c154253..ab6704ca204 100644
--- a/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
+++ b/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
@@ -27,8 +27,8 @@ import org.jetbrains.kotlin.js.translate.utils.AnnotationsUtils
 import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.psi.KtNamedFunction
 import org.jetbrains.kotlin.resolve.DescriptorUtils
-import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
 import org.jetbrains.kotlin.resolve.checkers.DeclarationChecker
+import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
 import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
 import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.types.typeUtil.isSubtypeOf
@@ -68,12 +68,12 @@ internal abstract class AbstractNativeIndexerChecker(
     override fun additionalCheck(declaration: KtNamedFunction, descriptor: FunctionDescriptor, diagnosticHolder: DiagnosticSink) {
         val parameters = descriptor.valueParameters
         val builtIns = descriptor.builtIns
-        if (parameters.size > 0) {
-            val firstParamClassDescriptor = DescriptorUtils.getClassDescriptorForType(parameters.get(0).type)
-            if (firstParamClassDescriptor != builtIns.string &&
-                !DescriptorUtils.isSubclass(firstParamClassDescriptor, builtIns.number)
-            ) {
-                diagnosticHolder.report(ErrorsJs.NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER.on(declaration.valueParameters.first(), indexerKind))
+        if (parameters.isNotEmpty()) {
+            val firstParamType = parameters.first().type
+            if (!KotlinBuiltIns.isString(firstParamType) && !firstParamType.isSubtypeOf(builtIns.number.defaultType)) {
+                diagnosticHolder.report(
+                    ErrorsJs.NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER.on(declaration.valueParameters.first(), indexerKind)
+                )
             }
         }