Landslide is one of the major geological hazards which seriously endangers the safety of human life and property. Site investigation for landslide prevention and control is important basic work in landslide prevention and control design. In this paper, the engineering geological surveying and investigation of the landslide area were carried out for the Pinghe County Xihuan Road landslide prevention and control project in Fujian Province. With engineering geological drilling results, the cause of landslides, and the calculation and evaluation of landslide stability were analyzed with proper prevention measures proposed. Inferring the position of the sliding surface, determining the geotechnical design parameters, and selecting the appropriate safety factor are very important for comprehensive prevention and control of landslides.