The traffic jam has become more serious at the multi-forked road intersection, and the conventional pre-timed control is less efficiencies to the congestion problem. In this paper, the new traffic signal control system for multi-forked road is proposed. Firstly, the cellular automaton (CA) model is used to develop a traffic simulator for multi-forked road. Next, the stochastic model of traffic jam is built up. In addition, new traffic signal control algorithm is designed using the optimization technique, Genetic Algorithm (GA). Finally, the effectiveness of the proposed method is shown using the actual traffic data with traffic simulator.