diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -330,7 +330,7 @@
   const FormatToken &Current = *State.NextToken;
   const FormatToken &Previous = *Current.Previous;
   if (Style.BraceWrapping.BeforeLambdaBody && Current.CanBreakBefore &&
-      Current.is(TT_LambdaLBrace)) {
+      Current.is(TT_LambdaLBrace) && Previous.isNot(TT_LineComment)) {
     auto LambdaBodyLength = getLengthToMatchingParen(Current, State.Stack);
     return (LambdaBodyLength > getColumnLimit(State));
   }
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
@@ -14587,6 +14587,30 @@
                LLVMWithBeforeLambdaBody);
 }
 
+TEST_F(FormatTest, LambdaWithLineComments) {
+  FormatStyle LLVMWithBeforeLambdaBody = getLLVMStyle();
+  LLVMWithBeforeLambdaBody.BreakBeforeBraces = FormatStyle::BS_Custom;
+  LLVMWithBeforeLambdaBody.BraceWrapping.BeforeLambdaBody = true;
+  LLVMWithBeforeLambdaBody.AllowShortLambdasOnASingleLine =
+      FormatStyle::ShortLambdaStyle::SLS_All;
+
+  verifyFormat("auto k = []() { return; }", LLVMWithBeforeLambdaBody);
+  verifyFormat("auto k = []() // comment\n"
+               "{ return; }",
+               LLVMWithBeforeLambdaBody);
+  verifyFormat("auto k = []() /* comment */ { return; }",
+               LLVMWithBeforeLambdaBody);
+  verifyFormat("auto k = []() /* comment */ /* comment */ { return; }",
+               LLVMWithBeforeLambdaBody);
+  verifyFormat("auto k = []() // X\n"
+               "{ return; }",
+               LLVMWithBeforeLambdaBody);
+  verifyFormat(
+      "auto k = []() // XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\n"
+      "{ return; }",
+      LLVMWithBeforeLambdaBody);
+}
+
 TEST_F(FormatTest, EmptyLinesInLambdas) {
   verifyFormat("auto lambda = []() {\n"
                "  x(); //\n"