diff --git a/clang/lib/Format/FormatToken.h b/clang/lib/Format/FormatToken.h
index b683660f350a..980c7be81d6b 100644
--- a/clang/lib/Format/FormatToken.h
+++ b/clang/lib/Format/FormatToken.h
@@ -528,6 +528,7 @@ struct AdditionalKeywords {
     kw_final = &IdentTable.get("final");
     kw_override = &IdentTable.get("override");
     kw_in = &IdentTable.get("in");
+    kw_of = &IdentTable.get("of");
     kw_CF_ENUM = &IdentTable.get("CF_ENUM");
     kw_CF_OPTIONS = &IdentTable.get("CF_OPTIONS");
     kw_NS_ENUM = &IdentTable.get("NS_ENUM");
@@ -571,6 +572,7 @@ struct AdditionalKeywords {
   IdentifierInfo *kw_final;
   IdentifierInfo *kw_override;
   IdentifierInfo *kw_in;
+  IdentifierInfo *kw_of;
   IdentifierInfo *kw_CF_ENUM;
   IdentifierInfo *kw_CF_OPTIONS;
   IdentifierInfo *kw_NS_ENUM;
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 9dcda5d3839e..d5d7146aaa41 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -2037,7 +2037,7 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
       return true;
   } else if (Style.Language == FormatStyle::LK_JavaScript) {
     if (Left.isOneOf(Keywords.kw_let, Keywords.kw_var, TT_JsFatArrow,
-                     Keywords.kw_in))
+                     Keywords.kw_in, Keywords.kw_of))
       return true;
     if (Left.is(tok::kw_default) && Left.Previous &&
         Left.Previous->is(tok::kw_export))
diff --git a/clang/unittests/Format/FormatTestJS.cpp b/clang/unittests/Format/FormatTestJS.cpp
index 7fad83aab12a..e08c876a5c67 100644
--- a/clang/unittests/Format/FormatTestJS.cpp
+++ b/clang/unittests/Format/FormatTestJS.cpp
@@ -595,6 +595,8 @@ TEST_F(FormatTestJS, ReturnStatements) {
 TEST_F(FormatTestJS, ForLoops) {
   verifyFormat("for (var i in [2, 3]) {\n"
                "}");
+  verifyFormat("for (var i of [2, 3]) {\n"
+               "}");
 }
 
 TEST_F(FormatTestJS, AutomaticSemicolonInsertion) {
@@ -758,6 +760,7 @@ TEST_F(FormatTestJS, TypeAnnotations) {
   verifyFormat("function x(): {x: string} {\n  return {x: 'x'};\n}");
   verifyFormat("function x(y: string): string {\n  return 'x';\n}");
   verifyFormat("for (var y: string in x) {\n  x();\n}");
+  verifyFormat("for (var y: string of x) {\n  x();\n}");
   verifyFormat("function x(y: {a?: number;} = {}): number {\n"
                "  return 12;\n"
                "}");