A novel accurate automated registration technique for infrared images based on the optical flow field analysis was presented. The technique can be preformed with two processes. Firstly the registration of background area of two images is finished based on the computation of global optical flow field. Then a hierarchical coarse-to-fine matching algorithm is used to extract the feature points of moving targets in two images. The registration of moving targets is finished using method of least squares which computes the transforming parameters of moving targets based on two set of feature points extracted. The simulation experiments for infrared images in some fields show that the method is accurate and robust to motion of scene.