diff --git a/clang-tools-extra/clangd/refactor/tweaks/AddUsing.cpp b/clang-tools-extra/clangd/refactor/tweaks/AddUsing.cpp
--- a/clang-tools-extra/clangd/refactor/tweaks/AddUsing.cpp
+++ b/clang-tools-extra/clangd/refactor/tweaks/AddUsing.cpp
@@ -152,12 +152,14 @@
     if (SM.isBeforeInTranslationUnit(Inputs.Cursor, U->getUsingLoc()))
       // "Usings" is sorted, so we're done.
       break;
-    if (U->getQualifier()->getAsNamespace()->getCanonicalDecl() ==
-            QualifierToRemove.getNestedNameSpecifier()
-                ->getAsNamespace()
-                ->getCanonicalDecl() &&
-        U->getName() == Name) {
-      return InsertionPointData();
+    if (const auto *Namespace = U->getQualifier()->getAsNamespace()) {
+      if (Namespace->getCanonicalDecl() ==
+              QualifierToRemove.getNestedNameSpecifier()
+                  ->getAsNamespace()
+                  ->getCanonicalDecl() &&
+          U->getName() == Name) {
+        return InsertionPointData();
+      }
     }
 
     // Insertion point will be before last UsingDecl that affects cursor
diff --git a/clang-tools-extra/clangd/unittests/TweakTests.cpp b/clang-tools-extra/clangd/unittests/TweakTests.cpp
--- a/clang-tools-extra/clangd/unittests/TweakTests.cpp
+++ b/clang-tools-extra/clangd/unittests/TweakTests.cpp
@@ -2884,6 +2884,17 @@
 void fun() {
   yy();
 }
+)cpp"},
+            // Existing using with non-namespace part.
+            {R"cpp(
+#include "test.hpp"
+using one::two::ee::ee_one;
+one::t^wo::cc c;
+)cpp",
+             R"cpp(
+#include "test.hpp"
+using one::two::cc;using one::two::ee::ee_one;
+cc c;
 )cpp"}};
   llvm::StringMap<std::string> EditedFiles;
   for (const auto &Case : Cases) {
@@ -2892,7 +2903,7 @@
 namespace one {
 void oo() {}
 namespace two {
-enum ee {};
+enum ee {ee_one};
 void ff() {}
 class cc {
 public: