Unmanned aerial vehicle (UAV) is a typical low altitude, slow and small (LSS) target. To detect and track this kind of target, a high resolution radar is usually used. In high resolution radar tracking algorithm, scatterers clustering is a key process which has a significant impact on the final performance. However, the lack of theoretical principle for clustering threshold has long been a problem. In this paper, a method based on Hough transform was proposed to improve the detection and tracking performance. By making use of the linear distributed micro Doppler features, the method is able to detect and recognize a UAV simultaneously, thus reduce the limitations on scatterers clustering. Experiment results show that the method can track a UAV continuously and steadily, and improve the tracking accuracy.