Abstract: In order to solve the arithmetic problem of non-rigid and large displacement optical flow, an improved arithmetic was proposed based on descriptor matching for optical flow. In the method, a novel data term was put forward firstly to adaptively select invariable hypothesizes for each pixel. And then, the traditional isotropic smoothness term was optimized to be the anisotropic one for the optical flow estimation of image details. Furthermore, the descriptor matching was applied to optical flow fields, taking advantage of the robust ability of descriptor matching to produce some large displacement correspondences and the ability of dense optical flow. At last, a quantitative analysis of the approach was performed on MPI Sintel.The results show that the proposed method can realize accurate estimation of non-rigid and large displacement optical flow. And the method is superior to LDOF with a relative gain of 18.9% for AAE and 21.9% for AEPE in market_5.