To study the dynamic mechanical properties of Polycarbonate/Acrylonitrile-Butadiene-Styrene (PC/ABS for short) , tensile experiments of PC/ABS material with 5:5 mixing ratio of PC to ABS under quasi-static state and medium and low strain rates in normal temperature environment were developed by using the static material testing machine and the high velocity hydraulic servo-testing machine. The true stress-strain curves of the material at the strain rate of 0.002 /s, 0.017 /s, 0.12 /s, 1.2 /s, 12.8 /s and 130 /s were obtained. The results show that the material has strain softening and hardening effects, and exhibits obvious strain rate sensitivity properties. The dynamic constitutive equation of PC/ABS material was established by fitting the parameters of J-C model based on experimental data. The fitting results are in good agreement with the experimental results, and can characterize the dynamic tensile mechanical behavior of PC/ABS in plastic segment well.