Abstract: Now many matching algorithms have made the frontal-parallel assumption,but this assumption does not conform to the actual scene of tilt surfaces.In order to address this issue,a mathematical model is illustrated to conclude that tilt surfaces in the environment have corresponding slanted disparity surfaces in the DSI (Disparity Space Image),which helps to find the proper disparity plane parameters of slanted support window.An improved algorithm based on cross aggregation is proposed.The algorithm is evaluated using the Toyota Technical Institute at Chicago (KITTI) benchmarks.The results show that the proposed algorithm can efficiently improve the tilt surfaces in the scene matching precision and execution efficiency.