Registration method based on optical flow model is very suitable to time-sequence images,but the assumption of constant brightness at a point makes it only be used to make registration for signal-modal images.So an exact histogram specification method is proposed to transform MR-PD model to MR-T2 modal before registration based on optical flow model.If the difference between two images is large the registration result could not be ideal because this registration method is mainly used to correct the light deformation between time-sequence images,so information which reflects the structural feature of image is taken to improve optical flow model,that is,image landmarks are utilized to produce an additional external-force for optical flow model to get ideal registration parameters.Experimental results demonstrate that the improved method can realize accurate registration of multi-modality time-sequence MR images between which there is large difference.