The large mudskipper is generally 10-20 cm in length and 20-50 grams in weight. The large mudskipper has an elongated body, flat sides, a large head, and a nearly cylindrical shape. The eyes are small and high, close to each other, protruding above the top of the head, and the lower eyelids are well developed. The mouth is roughly oblique, the two jaws are of equal length, and each jaw has one row of teeth. The maxillary teeth are conical, and the front three teeth are canine-shaped; the mandibular teeth are oblique to the outside, almost lying. Body covered with small round scales, no lateral line. The base of the pectoral fins is broad, the muscular stalk is developed, and the pelvic fins are healed into a sucker.

The big mudskipper has a dark brown body with small blue dots on the dorsal and caudal fins. Body dark brown. Belly grey. There are 6 black stripes on the back, irregular green-brown spots all over the body, two dorsal fins, and the first dorsal fin is very small. There are only 5 spines, and the ends of the spines are elongated in filaments, of which the third spine is the longest; the second dorsal and anal fins are long, and their lengths are roughly equal. The caudal fin is wedge-shaped and broad, the second dorsal fin has three usual gray-white horizontal lines, and the pectoral fin has a yellow-green worm-like pattern, which is very showy.