Abstract: A compensated Monte-Carlo collision model(CMCC) was proposed, which took the average collision times computed from normal distribution as the probability of single particle collision during a time step. Hereby the ignored multi-time collisions were compensated by additive single collisions. The electron motion in discharged He gas was simulated with CMCC model on different reduced field conditions. Simulation results showed that CMCC model with long time step got the same electron velocity distribution and temperature as conventional MCC model with short time step. It was proved that the CMCC model had high efficiency especially for PIC simulation of high pressure gas discharges.