Epinephelus bruneus has an elongate body which has a
standard length which is 3.0 to 3.6 times its depth. The dorsal profile of the head between the eyes is convex. The preopercle has an angle where the serrations are notably enlarged. There is a small spine on the upper edge of the gill cover and this upper edge is convex. The
dorsal fin contains 11 spines and 13-15 soft rays while the
anal fin has 3 spines and 8 soft rays. It has 64-72 scales in its
lateral line. The larger adults are dark greyish brown in colour, and may be marked with faint blotches on their nbacks, although these may be absent. They also have a covering of small grey spots on their bodies which form short longitudinal lines and creating a mottled pattern. The lower margin of the anal fin and the lower corner of caudal fin have white edges. The juveniles are pale yellowish brown in colour, with 6 irregular, diagonal dark bars within which there are irregular pale spots. The first of these bars extends from nape to eye and the last is on the caudal peduncle. There are 3 dark brown bands which radiate from lower part of eye and some juveniles have greenish yellow membranes between the rearmost spines of the dorsal fin. The maximum published
total length for this species is , although the most common length is around , and the maximum recorded weight is . ==Distribution==