In order to solve the shortcomings of existing target tracking algorithms applied in MIS, this invention does some optimization based on TLST model and proposes a novel target tracking algorithm combined with KCF and region growing algorithm. Compared with the traditional TLST, our optimized multi-model TLST reduces the complexity of computation and has a better performance on dealing with singular point. Then, through combining KCF and region growing algorithm, the rigid surgical tool can be detected more accurately. Besides, this invention proposes a novel feature extraction which can be optionally used to do further examination.