The influence of vehicle platform deformation on the measuring errors of a theodolite was analyzed,then the platform deformation was divided into two types of translation and rotation. A numerical simulation was performed to demonstrate that the platform rotation deformation was the main factors to affect the measuring error of the platform.A simulation model of vehicle theodolite between measuring error and rotation deformation was established,and the influence of the target location and rotation deformation on measuring errors was simulated based on the model. Furthermore,the platform angular deviation was measured by a self-collimation measurement system based on Moiré fringe and the platform angular rotation was measured by a inclinometer, which then was validated by experiments.Obtained data show that this method can effectively compensate static angle measuring errors come from the deformation of vehicle platform, and can improve the azimuth precision to 103.7″and elevation precision to 89.4″. It provides a theoretical reference and technical support for the high-precision measurement of vehicle theodolites.