Abstract: An improved optical flow model within the differential framework is employed in brain image registration.Aiming at eliminating the severe image blurring caused by the Horn model,the anisotropic flow-driven diffusion,which is able to preserve edges and enhance coherence,is used as the regularization term to keep the image feature during the registration process.The data term employs the nonquadratic penalization function to improve the model's robustness.Our improved model is applied to register brain images,and more accurate and robust results are obtained.