Eutrigla gurnardus is a large member of the sea robin family reaching up to 30 cm (and rarely up to 50 cm) in length. It has a large head with a sloping forehead and a body that tapers towards the tail. Two dorsal fins are present on the back. The first, which is much smaller than the second has 7-10 spines and large black mark near the top. The second dorsal fin and its symmetrical anal fin counterpart both have 18-20 rays. The pectoral fins are short and barely reach the anal fin. The caudal fin is short and truncate. The grey gurnard is usually greyish-brown in colour with a red tinge on the back and sides. Small white spots are usually present on the sides and the underside is cream in colour.