This paper proposes a two-direction green wave control algorithm of traffic signal based on particle swarm optimization. The traffic flow model of queuing length and two-direction green wave control object function were built. The signal split and the phase offset were optimized by particle swarm optimization. The simulation result with traffic data collected from Liansheng Road in Dongguan City proved this method was effective and practical. Compared with graphical method and actuate signal control, the proposed algorithm could effectively reduce delaying time and shorten queuing length.