Abstract: Modeling method for vehicle's four-wheel alignment measurement plane is proposed in this paper, with the purpose of overcoming the difficulty of the present measurement for vehicle's four-wheel alignment that was severely affected by the measuring environment. First, by moving vehicles, different image information of the wheel target was obtained during the moving of the vehicle. Second, with the spatial vector method, the measurement plane was dynamically created, and the wheel's axle data were calculated, as a result this method get the four-wheel alignment parameters and solves the problem that the error is too big when measuring level is not even or measurement environment interfere with the result. Moreover, with the new method, the measurement procedure is simplified. Test shows that the four-wheel alignment parameters are not affected by the lifting equipment and site, and the margin of error is between- 0.05° and 0.05°.