Two properties of Super-Resolution calculation for image super-resolution reconstruction are proved,and a new texture adaptive super-resolution algorithm is proposed based on MAP(Maximum a posteriori)model.In Super-Resolution reconstruction process,an initial high resolution image with higher quality is calculated firstly by approximate calculation,and then trilateral model is applied as a regularization term in MAP model to preserve slope edge and roof edge.The fusion parameter and regularization parameter can be adaptively computed by image texture without manual adjustment.Simulation results confirm the effectiveness of this algorithm and demonstrate its superiority to other super-resolution algorithms.