diff --git a/library/init/lean/parser/parser.lean b/library/init/lean/parser/parser.lean
index db68b20200..392599b26e 100644
--- a/library/init/lean/parser/parser.lean
+++ b/library/init/lean/parser/parser.lean
@@ -89,7 +89,7 @@ private def expectedToString : List String → String
 protected def toString (e : Error) : String :=
 let unexpected := if e.unexpected == "" then [] else ["unexpected " ++ e.unexpected];
 let expected   := if e.expected == [] then [] else ["expected " ++ expectedToString e.expected];
-";".intercalate $ unexpected ++ expected
+"; ".intercalate $ unexpected ++ expected
 
 instance : HasToString Error := ⟨Error.toString⟩