The average weight of Chinese water snakes is over 150g, the largest individual can reach over 750g, and the body length is about 60cm. Chinese water snakes have large heads and stomachs, and their food intake is amazing. This is a non-toxic snake.

Chinese water snake has dark gray-brown back with irregular black spots, yellowish belly with black spots and slightly flat tail. Scattered with slightly vertical black spots, the first line on both sides is black, and the second and third lines are white; The ventral surface is yellow, and there are black spots on the front edge of each ventral scale. The trunk is cylindrical and the tail is short. The nasal scales are single, the left and right nasal scales are tangent, and the nostrils are in the posterior position; Small eyes, preorbital scale 1, retroorbital scale 2, temporal scale1+2; The scale of the upper lip is 7 (8,9), 3-1-3 (4,5). The dorsal scale is smooth, with line 23 (25)-23 (25)-19; Abdominal scale139-155; Anal scale dichotomy; Secondary tail scale 38-5 1 pair.