Abstract: Penaeus vannameis were pretreated with mixtures of different mass fraction of ice and salt for different periods of time. Measurement indexs were shelling time, total volatile basic nitrogen, activity of ATP-ase, hardness, tension between shell and muscle, elasticity of the meat and temperature variation. Combined with sensory evaluation, it was confirmed that the optimum pretreatment condition of shelling was 0.5 hour of pretreatment with 4% of salt and ice mixture. At which condition, the body temperature was-0.05℃, shelling time was 7.72min, elasticity was 3.71mm, hardness was 10.43N, tension was 1.7N, total volatile basic nitrogen content was 4.79mg/100g, ATP-ase was 0.063U/mg, and the shelled shrimp smelled normal and showed inherent color. The study provided with technical support for mechanical shelling of Penaeus vannamei.