diff --git a/clang/lib/Index/IndexingContext.cpp b/clang/lib/Index/IndexingContext.cpp
index 2f54667e85ed..754bc84ff4b2 100644
--- a/clang/lib/Index/IndexingContext.cpp
+++ b/clang/lib/Index/IndexingContext.cpp
@@ -130,7 +130,8 @@ bool IndexingContext::isTemplateImplicitInstantiation(const Decl *D) {
   } else if (const auto *ED = dyn_cast<EnumDecl>(D)) {
     if (ED->getInstantiatedFromMemberEnum())
       TKind = ED->getTemplateSpecializationKind();
-  } else if (isa<FieldDecl>(D) || isa<TypedefNameDecl>(D)) {
+  } else if (isa<FieldDecl>(D) || isa<TypedefNameDecl>(D) ||
+             isa<EnumConstantDecl>(D)) {
     if (const auto *Parent = dyn_cast<Decl>(D->getDeclContext()))
       return isTemplateImplicitInstantiation(Parent);
   }
@@ -193,6 +194,13 @@ static const Decl *adjustTemplateImplicitInstantiation(const Decl *D) {
           return BaseND;
       }
     }
+  } else if (const auto *ECD = dyn_cast<EnumConstantDecl>(D)) {
+    if (const auto *ED = dyn_cast<EnumDecl>(ECD->getDeclContext())) {
+      if (const EnumDecl *Pattern = ED->getInstantiatedFromMemberEnum()) {
+        for (const NamedDecl *BaseECD : Pattern->lookup(ECD->getDeclName()))
+          return BaseECD;
+      }
+    }
   }
   return nullptr;
 }
diff --git a/clang/test/Index/Core/index-instantiated-source.cpp b/clang/test/Index/Core/index-instantiated-source.cpp
index 5cfdbac719bd..7a810fbdf3a8 100644
--- a/clang/test/Index/Core/index-instantiated-source.cpp
+++ b/clang/test/Index/Core/index-instantiated-source.cpp
@@ -46,6 +46,7 @@ public:
     enum Enum {
 // CHECK: [[@LINE-1]]:10 | enum/C | Enum | c:@ST>2#T#T@TemplateClass@S@NestedType@E@Enum |
       EnumCase
+// CHECK: [[@LINE-1]]:7 | enumerator/C | EnumCase | c:@ST>2#T#T@TemplateClass@S@NestedType@E@Enum@EnumCase |
     };
   };
 };
@@ -82,4 +83,6 @@ void canonicalizeInstaniationReferences(TemplateClass<int, float> &object) {
 
   TT::NestedType::Enum nestedEnum;
 // CHECK: [[@LINE-1]]:19 | enum/C | Enum | c:@ST>2#T#T@TemplateClass@S@NestedType@E@Enum |
+  (void)TT::NestedType::Enum::EnumCase;
+// CHECK: [[@LINE-1]]:31 | enumerator/C | EnumCase | c:@ST>2#T#T@TemplateClass@S@NestedType@E@Enum@EnumCase |
 }