diff --git a/clang-tools-extra/clangd/IncludeCleaner.cpp b/clang-tools-extra/clangd/IncludeCleaner.cpp
--- a/clang-tools-extra/clangd/IncludeCleaner.cpp
+++ b/clang-tools-extra/clangd/IncludeCleaner.cpp
@@ -353,20 +353,29 @@
 std::vector<include_cleaner::SymbolReference>
 collectMacroReferences(ParsedAST &AST) {
   const auto &SM = AST.getSourceManager();
-  //  FIXME: !!this is a hacky way to collect macro references.
-  std::vector<include_cleaner::SymbolReference> Macros;
   auto &PP = AST.getPreprocessor();
-  for (const syntax::Token &Tok :
-       AST.getTokens().spelledTokens(SM.getMainFileID())) {
-    auto Macro = locateMacroAt(Tok, PP);
-    if (!Macro)
-      continue;
-    if (auto DefLoc = Macro->Info->getDefinitionLoc(); DefLoc.isValid())
-      Macros.push_back(
-          {include_cleaner::Macro{/*Name=*/PP.getIdentifierInfo(Tok.text(SM)),
-                                  DefLoc},
-           Tok.location(), include_cleaner::RefType::Explicit});
+  std::vector<include_cleaner::SymbolReference> Macros;
+  for (const auto &[_, Refs] : AST.getMacros().MacroRefs) {
+    for (const auto &Ref : Refs) {
+      SourceLocation Loc = SM.getLocForStartOfFile(SM.getMainFileID())
+                               .getLocWithOffset(Ref.StartOffset);
+      const auto *Tok = AST.getTokens().spelledTokenAt(Loc);
+      if (!Tok)
+        continue;
+      auto Macro = locateMacroAt(*Tok, PP);
+      if (!Macro)
+        continue;
+
+      if (auto DefLoc = Macro->NameLoc; DefLoc.isValid())
+        Macros.push_back(
+            {include_cleaner::Macro{
+                 /*Name=*/PP.getIdentifierInfo(Tok->text(SM)), DefLoc},
+             Tok->location(),
+             Ref.InConditionalDirective ? include_cleaner::RefType::Ambiguous
+                                        : include_cleaner::RefType::Explicit});
+    }
   }
+
   return Macros;
 }
 
diff --git a/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp b/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
--- a/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
+++ b/clang-tools-extra/clangd/unittests/IncludeCleanerTests.cpp
@@ -186,6 +186,10 @@
 #define DEF(X) const Foo *X;
 #define BAZ(X) const X x
 
+// No missing include insertion for ambiguous macro refs.
+#if defined(FOO)
+#endif
+
   void foo() {
     $b[[b]]();