diff --git a/src/Lean/Parser/Term.lean b/src/Lean/Parser/Term.lean
index 6ffe3e4be7..e71e7788bb 100644
--- a/src/Lean/Parser/Term.lean
+++ b/src/Lean/Parser/Term.lean
@@ -870,7 +870,7 @@ def matchExprElseAlt (rhsParser : Parser) := leading_parser "| " >> ppIndent (ho
 def matchExprAlts (rhsParser : Parser) :=
   leading_parser withPosition $
     many (ppLine >> checkColGe "irrelevant" >> notFollowedBy (symbol "| " >> " _ ") "irrelevant" >> matchExprAlt rhsParser)
-    >> (ppLine >> checkColGe "irrelevant" >> matchExprElseAlt rhsParser)
+    >> (ppLine >> checkColGe "else-alternative for `match_expr`, i.e., `| _ => ...`" >> matchExprElseAlt rhsParser)
 @[builtin_term_parser] def matchExpr := leading_parser:leadPrec
   "match_expr " >> termParser >> " with" >> ppDedent (matchExprAlts termParser)
 
diff --git a/tests/lean/3989_1.lean b/tests/lean/3989_1.lean
new file mode 100644
index 0000000000..adbbfb2f42
--- /dev/null
+++ b/tests/lean/3989_1.lean
@@ -0,0 +1,3 @@
+def foo (ty : Expr) : MetaM Expr :=
+  match_expr ty with
+  | Nat => sorry
diff --git a/tests/lean/3989_1.lean.expected.out b/tests/lean/3989_1.lean.expected.out
new file mode 100644
index 0000000000..188b2bb20a
--- /dev/null
+++ b/tests/lean/3989_1.lean.expected.out
@@ -0,0 +1 @@
+3989_1.lean:4:0: error: expected else-alternative for `match_expr`, i.e., `| _ => ...`
diff --git a/tests/lean/3989_2.lean b/tests/lean/3989_2.lean
new file mode 100644
index 0000000000..962415b0c1
--- /dev/null
+++ b/tests/lean/3989_2.lean
@@ -0,0 +1,6 @@
+def foo (ty : Expr) : MetaM Expr :=
+  match_expr ty with
+  | Nat => sorry
+  | BitVec n => sorry
+
+#check Nat
diff --git a/tests/lean/3989_2.lean.expected.out b/tests/lean/3989_2.lean.expected.out
new file mode 100644
index 0000000000..4e1569eb91
--- /dev/null
+++ b/tests/lean/3989_2.lean.expected.out
@@ -0,0 +1,2 @@
+3989_2.lean:6:0: error: expected else-alternative for `match_expr`, i.e., `| _ => ...`
+Nat : Type