diff --git a/executor/insert_common.go b/executor/insert_common.go
index 8440242f1dad5..862c82a88da90 100644
--- a/executor/insert_common.go
+++ b/executor/insert_common.go
@@ -32,6 +32,7 @@ import (
 	"github.com/pingcap/tidb/parser/ast"
 	"github.com/pingcap/tidb/parser/model"
 	"github.com/pingcap/tidb/parser/mysql"
+	"github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/sessiontxn"
@@ -771,7 +772,16 @@ func setDatumAutoIDAndCast(ctx sessionctx.Context, d *types.Datum, id int64, col
 	var err error
 	*d, err = table.CastValue(ctx, *d, col.ToInfo(), false, false)
 	if err == nil && d.GetInt64() < id {
-		// Auto ID is out of range, the truncated ID is possible to duplicate with an existing ID.
+		// Auto ID is out of range.
+		sc := ctx.GetSessionVars().StmtCtx
+		insertPlan, ok := sc.GetPlan().(*core.Insert)
+		if ok && sc.TruncateAsWarning && len(insertPlan.OnDuplicate) > 0 {
+			// Fix issue #38950: AUTO_INCREMENT is incompatible with mysql
+			// An auto id out of range error occurs in `insert ignore into ... on duplicate ...`.
+			// We should allow the SQL to be executed successfully.
+			return nil
+		}
+		// The truncated ID is possible to duplicate with an existing ID.
 		// To prevent updating unrelated rows in the REPLACE statement, it is better to throw an error.
 		return autoid.ErrAutoincReadFailed
 	}
diff --git a/executor/writetest/write_test.go b/executor/writetest/write_test.go
index ebeaaa388e269..32939a1b16033 100644
--- a/executor/writetest/write_test.go
+++ b/executor/writetest/write_test.go
@@ -592,6 +592,25 @@ commit;`
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1526 Table has no partition for value 3"))
 }
 
+func TestIssue38950(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	var cfg kv.InjectionConfig
+	tk := testkit.NewTestKit(t, kv.NewInjectedStore(store, &cfg))
+	tk.MustExec("use test;")
+	tk.MustExec("drop table if exists t; create table t (id smallint auto_increment primary key);")
+	tk.MustExec("alter table t add column c1 int default 1;")
+	tk.MustExec("insert ignore into t(id) values (194626268);")
+	require.Empty(t, tk.Session().LastMessage())
+
+	tk.MustQuery("select * from t").Check(testkit.Rows("32767 1"))
+
+	tk.MustExec("insert ignore into t(id) values ('*') on duplicate key update c1 = 2;")
+	require.Equal(t, int64(2), int64(tk.Session().AffectedRows()))
+	require.Empty(t, tk.Session().LastMessage())
+
+	tk.MustQuery("select * from t").Check(testkit.Rows("32767 2"))
+}
+
 func TestInsertOnDup(t *testing.T) {
 	store := testkit.CreateMockStore(t)
 	var cfg kv.InjectionConfig