Sansuojin snake belongs to the national three possessions protected wild animals. The back is gray or yellow, with a black horizontal stripe on the occiput. It is named after the three radial black lines on the head. The front half of the body has 2-3 or 4 black longitudinal stripes. The upper pair is wider and the ventral surface is light brown.

Sansuo Jin SnakeLarge and full Length 1590(1320+270)mm, male 104～138+29～ 32 cm, female 116~137.5+28~31.7 cm. One cheek scale, 1 preorbital scale, 2 retroorbital scales , temporal scale (2+2). 9 upper lip scales, 4-2-3 type, 10 lower lip scales The first four to the first six are connected to the anterior chin. Dorsal scales with several central rows of ribs, 19-19-17 rows, ventral 231 scales, complete anal scales, double row of lower tail scales, 93 pairs . Living in mountains, plains and hilly areas below 700m above sea level, it is more common on soil slopes, field foundations and roadsides, and sometimes breaks into residential areas.