In order to correct the laser pointing errors caused by the axial errors for a level mounting laser transmitter system, a new laser pointing error correction model was built by using the correction method used in the pointing error correction of a photoelectric theodolite,and the error transfer behavior between shafts and optical path was investigated intensively. Firstly, the opto-mechanical structure and modeling theory were introduced, and the transformation matrixes of mirrors were presented. Then, by constructing two 3D coordinates in which the laser beam was considered as a unit vector, the laser pointing model was established by linear coordinate transformation and linear vector transformation. Furthermore,the undetermined coefficients in the laser pointing model were obtained by least square fitting.Finally, the TV tracking system whose optical axis was actually considered as an ideal one in the laser transmitter system was used to measure the laser pointing error. Experimental results indicate that the laser pointing precision of the level mounting laser transmitter system is up to 3.1″ and 9.7″ in 2 specific orbits and a zenith region, respectively, which satisfies the requirement of the system design for the accuracy.