diff --git a/explorer/syntax/parser.ypp b/explorer/syntax/parser.ypp
index e01472abf95f..638d5297ff93 100644
--- a/explorer/syntax/parser.ypp
+++ b/explorer/syntax/parser.ypp
@@ -59,9 +59,9 @@
   #include <cstdlib>
   #include <vector>
 
-  #include "common/check.h"
   #include "explorer/syntax/parse_and_lex_context.h"
   #include "llvm/ADT/StringExtras.h"
+  #include "llvm/Support/FormatVariadic.h"
   #include "llvm/Support/raw_ostream.h"
 }  // %code top
 
@@ -349,11 +349,18 @@ primary_expression:
     { $$ = arena->New<BoolLiteral>(context.source_loc(), false); }
 | sized_type_literal
     {
-      int val;
-      CARBON_CHECK(llvm::to_integer(llvm::StringRef($1).substr(1), val));
-      CARBON_CHECK($1[0] == 'i' && val == 32)
-          << "Only i32 is supported for now: " << $1;
-      $$ = arena->New<IntTypeLiteral>(context.source_loc());
+      int val = 0;
+      if (!llvm::to_integer(llvm::StringRef($1).substr(1), val)) {
+        context.RecordSyntaxError(
+            llvm::formatv("Invalid type literal: {0}", $1));
+        YYERROR;
+      } else if ($1[0] != 'i' || val != 32) {
+        context.RecordSyntaxError(
+            llvm::formatv("Only i32 is supported for now: {0}", $1));
+        YYERROR;
+      } else {
+        $$ = arena->New<IntTypeLiteral>(context.source_loc());
+      }
     }
 | SELF
     // TODO: Should we create a new TypeLiteral for `Self`?
diff --git a/explorer/testdata/basic_syntax/fail_invalid_integer_type.carbon b/explorer/testdata/basic_syntax/fail_invalid_integer_type.carbon
new file mode 100644
index 000000000000..be70267d3aec
--- /dev/null
+++ b/explorer/testdata/basic_syntax/fail_invalid_integer_type.carbon
@@ -0,0 +1,17 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// RUN: %{not} %{explorer} %s 2>&1 | \
+// RUN:   %{FileCheck} --match-full-lines --allow-unused-prefixes=false %s
+// RUN: %{not} %{explorer} --parser_debug --trace_file=- %s 2>&1 | \
+// RUN:   %{FileCheck} --match-full-lines --allow-unused-prefixes %s
+// AUTOUPDATE: %{explorer} %s
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK: COMPILATION ERROR: {{.*}}/explorer/testdata/basic_syntax/fail_invalid_integer_type.carbon:[[@LINE+1]]: Invalid type literal: i11111111111111111111111111
+  var x: i11111111111111111111111111 = 1;
+  return 0;
+}
diff --git a/explorer/testdata/basic_syntax/fail_unsupported_integer_type.carbon b/explorer/testdata/basic_syntax/fail_unsupported_integer_type.carbon
new file mode 100644
index 000000000000..e10d6c0a7655
--- /dev/null
+++ b/explorer/testdata/basic_syntax/fail_unsupported_integer_type.carbon
@@ -0,0 +1,17 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// RUN: %{not} %{explorer} %s 2>&1 | \
+// RUN:   %{FileCheck} --match-full-lines --allow-unused-prefixes=false %s
+// RUN: %{not} %{explorer} --parser_debug --trace_file=- %s 2>&1 | \
+// RUN:   %{FileCheck} --match-full-lines --allow-unused-prefixes %s
+// AUTOUPDATE: %{explorer} %s
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK: COMPILATION ERROR: {{.*}}/explorer/testdata/basic_syntax/fail_unsupported_integer_type.carbon:[[@LINE+1]]: Only i32 is supported for now: i64
+  var x: i64 = 1;
+  return 0;
+}