Steirastoma pustulata is a species of beetle in the family Cerambycidae.

Antennae (with the basal joint very thick) much longer than the insect.

Thorax rough, gibbous, and full of small pustules, two of which form an obtuse spine on the sides.

Elytra margined, and full of small pustules, having two spines fixed at their extremity, near the suture.

Body length about 1 inch (25 mm).