In accordance with an engineering project, aimed at the slope construction of highway tunnel at the entry or exit location under complex geological conditions, a slope protecting and strengthening method which can reduce rainwater seepage and decrease the risk of landslide effectively was discussed in the paper. The subsidence of the slope and the blasting shock were monitored in the process of slope excavation, and the information of monitoring was fed back timely to optimize the construction process. The method can provide a useful experience for similar projects.