Aiming at the problem that the fast tracking algorithm using spatio-temporal context (STC) will inevitably lead to drift and even lose the target in long-term tracking,a new algorithm based on spatio-temporal context that integrates long-term tracking with detecting is proposed in this paper.We track the target by the fast tracking algorithm,and the cascaded search strategy is introduced to the detecting part to relocate the target if the fast tracking fails.To a large extent,the proposed algorithm effectively improves the accuracy and stability of long-term tracking.Extensive experimental results on benchmark datasets show that the proposed algorithm can accurately track and relocate the target though the target is partially or completely occluded or reappears after being out of the scene.