Ennomos alniaria, the canary-shouldered thorn, is a moth of the family Geometridae.

The species was first described by Carl Linnaeus in his 1758 10th edition of Systema Naturae.

Resembles Ennomos quercinaria, but has a canary-yellow thorax.

The larva is brownish-grey, long and thin, with four raised cross-bands on the dorsal side.

The larvae feed on a number of deciduous trees including downy birch and silver birch, alder and goat willow.