Many measurement errors affect the positioning accuracy of the laser point cloud obtained from airborne laser scanning (ALS). These error factors exist together and influence each other. Therefore, it is of practical significance to find out them, and to analysis their impact sizes and make a sorting. The working principle of conical scanning mode airborne laser scanner is analyzed, and error factors affecting the positioning accuracy of laser point cloud are determined. Furthermore, the transfer relationship between the error factors and the three-dimensional (3D) coordinate errors of the laser point cloud is established. By using multiple linear regression method, regression equations between the error factors and the 3D coordinate errors are established, and the impact significance of each error factor on the 3D coordinate errors is quantitatively evaluated and further sorted. The study provides an important theoretical basis for compensating the significant error factors, so as to effectively improve position accuracy of laser point cloud.