diff --git a/clang-tools-extra/clangd/IncludeCleaner.h b/clang-tools-extra/clangd/IncludeCleaner.h
--- a/clang-tools-extra/clangd/IncludeCleaner.h
+++ b/clang-tools-extra/clangd/IncludeCleaner.h
@@ -33,11 +33,13 @@
 using ReferencedLocations = llvm::DenseSet<SourceLocation>;
 /// Finds locations of all symbols used in the main file.
 ///
-/// Uses RecursiveASTVisitor to go through main file AST and computes all the
-/// locations used symbols are coming from. Returned locations may be macro
-/// expansions, and are not resolved to their spelling/expansion location. These
-/// locations are later used to determine which headers should be marked as
-/// "used" and "directly used".
+/// - For non-macros uses RecursiveASTVisitor to go through main file AST and
+///   computes all the locations used symbols are coming from. Returned
+///   locations may be macro expansions, and are not resolved to their spelling
+///   or expansion location. These locations are later used to determine which
+///   headers should /   be marked as "used" and "directly used".
+/// - For macros iteratates over \p AST tokens and collects locations of the
+///   used macro definition.
 ///
 /// We use this to compute unused headers, so we:
 ///
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
@@ -7,9 +7,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "IncludeCleaner.h"
+#include "SourceCode.h"
 #include "support/Logger.h"
 #include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/Basic/SourceLocation.h"
+#include "clang/Tooling/Syntax/Tokens.h"
 
 namespace clang {
 namespace clangd {
@@ -133,13 +135,28 @@
   }
 };
 
+// Gets the tokens from the main file, iterates through them and adds definition
+// locations for the found macros.
+void findReferencedMacros(ParsedAST &AST, ReferencedLocations &Result) {
+  auto Tokens =
+      AST.getTokens().spelledTokens(AST.getSourceManager().getMainFileID());
+  for (const syntax::Token &Tok : Tokens) {
+    auto Macro = locateMacroAt(Tok, AST.getPreprocessor());
+    if (!Macro)
+      continue;
+    auto Loc = Macro->Info->getDefinitionLoc();
+    if (Loc.isValid())
+      Result.insert(Loc);
+  }
+}
+
 } // namespace
 
 ReferencedLocations findReferencedLocations(ParsedAST &AST) {
   ReferencedLocations Result;
   ReferencedLocationCrawler Crawler(Result);
   Crawler.TraverseAST(AST.getASTContext());
-  // FIXME(kirillbobyrev): Handle macros.
+  findReferencedMacros(AST, Result);
   return Result;
 }
 
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
@@ -103,6 +103,16 @@
           "struct ^X { enum ^Language { ^CXX = 42, Python = 9000}; };",
           "int Lang = X::CXX;",
       },
+      // Macros
+      {
+          "#define ^CONSTANT 42",
+          "int Foo = CONSTANT;",
+      },
+      {
+          "#define ^FOO x",
+          "#define BAR FOO",
+      },
+      // Misc
       {
           // When a type is resolved via a using declaration, the
           // UsingShadowDecl is not referenced in the AST.