In view of the difficulties of traditional slope monitoring methods, such as heavy workload, incomplete data, difficult model establishment, poor effect and low accuracy, a slope deformation monitoring method based on three-dimensional laser scanning technology and T-splines surface fitting is proposed in this paper. In this method, firstly, the 3D laser scanning technology is used to scan the slope in the field to obtain the slope data; then the processed point cloud data are fitted by T-splines to obtain the five phase high-precision surface model and analyze the deformation of the whole slope body; the shape variables of the stability monitoring points in the slope body are selected for consistency test with the total station measurement data. The experimental results prove that the slope deformation monitoring method combining three-dimensional laser scanning technology and T-spline surface fitting meets the requirements of slope deformation monitoring.