diff --git a/src/nsfns.m b/src/nsfns.m
index 8804a7df7cf..5ae2cc77bb2 100644
--- a/src/nsfns.m
+++ b/src/nsfns.m
@@ -3829,7 +3829,9 @@ handled fairly well by the NS libraries (displayed with distinct
 /* Make a Lisp string from an NSString.  */
 - (Lisp_Object)lispString
 {
-  return build_string ([self UTF8String]);
+  // make_string behaves predictably and correctly with UTF-8 input.
+  return make_string ([self UTF8String],
+                      [self lengthOfBytesUsingEncoding: NSUTF8StringEncoding]);
 }
 @end