The shape is a little like gecko, the body length is generally about 1 meter, the longest can reach 2 meters, the weight is 20-25 kg, the largest is 50 kg. Its head is broad and flat, and its surface has obvious verrucous granules. Small eyes, located on the back of the head, without eyelids, which is the result of long-term adaptation to underwater life and degradation. The arc-shaped cleft is very wide, and most of the jaws have fine teeth of similar size, which is conducive to feeding. The body is broad, flat and strong. The tail of the flattened side is very long. It is one third to one half of the body length. There are fins in the upper and lower parts of the tail. Short limbs, much like infant arms, are said to be another reason for calling it a doll fish. There are 4 fingers in the forelimbs and 5 toes in the hind limbs. There are slight webs between the fingers (toes) and no claws. The skin is smooth with small verrucous granules, which can secrete white pulpy mucus like pepper when stimulated. Longitudinal skin folds were found along the lateral axillary hip. Body color varies with habitat color, with brown, reddish-brown, black-brown on the back, dark irregular spots on the top and light brown or gray-white on the ventral surface.