This article is based on sliding-mode control and theory of finite-time stability in non-liner system. The fast terminal sliding-mode algorithm is used in designing a rapid converging guidance law with LOS constraint. This guidance law is compared with the traditional sliding-mode guidance law. The simulation shows that the former has superior dynamic property, and can meet the finite-time convergence and LOS constraint condition at the same time, with smooth trajectory and low power consumption. This terminal guidance law can effectively intercept the maneuvering targets.