In this paper, a microscopic simulation of traffic flow on a traffic signal network is developed. Its purpose is to apply to evaluation of signal control and various traffic operations such as right-turning lane. In this simulation, the speed and location of individual vehicle are renewed every short time period. Detailed behaviors of each vehicle such as deceleration and stoppage at red signal, departure and acceleration at green signal and car-following are reproduced. Turning traffic at signalized intersections and lane-change to adjacent lane or to right-turning lane are taken into consideration. It was found that it is possible to reproduce traffic situation on 4-lane streets of about 10 km length at the same computation speed as real time by using personal computer, and that it is possible to evaluate signal control and right-turning lane.