Taking the rapid statistics of the naked rock mass discontinuity of the slope of the Liqiu River as an example, the semi-automatic rapid statistics method with three-dimensional laser measurement was proposed. The combined measurement method of three-dimensional laser scanner and high-precision GPS, as well as the method of coordinate conversion of laser point cloud data and triangle grid reconstruction of slope surface were introduced. On this basis, the method of semi-automatic fitting applying three-dimensional laser point cloud and slope triangle grid to rock mass discontinuity was studied. With the relationship between rock mass discontinuity normal vector and occurrence, the density map, rose diagram, pole diagram and stereographic projection diagram could be drew.