Under the long-term load and non-uniform force, the steel structure will produce space deformation, among which the disturbance degree is an important measure index. Usually the total station instrument is used to collect some characteristic points on the steel structure axis to analyze and calculate. Because the steel structure characteristic point is difficult to capture, the measurement has the error, and the limited space discrete point is difficult to fully reflect the steel structure spatial deformation. Uses Leica RTC360 3D laser scanning to measure the disturbance of steel structure in the paper. It introduces its operation flow and data processing method. The 3D point cloud of each station is spliced into a whole by using the target, the spatial feature points and axes are extracted by the fitting method, and the spatial model is constructed by using 3D point cloud.