Tunable negative refraction photonic crystals have attracted much attention for their potential application value. The photonic crystal with a square lattice of Si cylinders surrounded by optically controlled liquid crystals is investigated. The plane wave expansion method is used to calculate the equi-frequency surface (EFS). The General Snell′s Law and EFS analysis method is used to ensure the ability of tunable refraction. A new photonic crystal filled with liquid crystal structure is designed. Numerical simulation result shows that this kind of tunable negative refraction photonic crystal filled with optically controlled liquid crystals can be achieved. Compared with electronically controlled one, this way has a faster response speed and a more simple structure, which may be used in optically controlled router and all optical networks.