diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -1881,7 +1881,7 @@
         }
       }
 
-      if (FormatTok->is(Keywords.kw_interface)) {
+      if (!Style.isCpp() && FormatTok->is(Keywords.kw_interface)) {
         if (parseStructLike())
           return;
         break;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -25429,6 +25429,13 @@
   verifyFormat("auto x = 5s .count() == 5;");
 }
 
+TEST_F(FormatTest, InterfaceAsClassMemberName) {
+  verifyFormat("class Foo {\n"
+               "  int interface;\n"
+               "  Foo::Foo(int iface) : interface{iface} {}\n"
+               "}");
+}
+
 } // namespace
 } // namespace test
 } // namespace format