This paper studied the deformation behavior of Polycarbonate (PC) sheet at temperature of -50,-20, 0,0, 60 ℃ and strain rate of 0.6,0.6,0.6,0.12 s-1, respectively. Based on tensile tests and parameter identification, a modified DSGZ constitution model was developed to describe PC mechanical properties at the temperature from -50 ℃ to 60 ℃, and the results show that the model can give much better description of PC mechanical deformation at low and medium temperature.