Hellula undalis, the cabbage webworm or Old World webworm, is a moth of the family Crambidae.

It is a widespread species which is found from Europe across Asia to the Pacific.

It was first described from Italy but it is a tropical or subtropical species only occasional in Europe.

The forewings are greyish-brown with wavy grey markings, a curved pale subterminal patch and a kidney shaped mark at one third.

The hindwings are pale, with the tip lighter.