Abstract: Based on the spatial geometric analysis, a mathematical model for measuring the kingpin angle was established, the detection mechanism of the measuring positioning parameters was studied, and a verification device for four-wheel alignment was designed. The device uses the spherical hinge structure to make the simulated kingpin backward and inward tilt independently, avoiding errors caused by interference in the synthetic motion. The dual-axis inclination angle sensor is used to realize the accurate measurement of the positioning parameters. The finite element modal analysis of the device was carried out by ANSYS software, the results showed that the stiffness and the inherent frequency and vibration model of the first six orders meet the requirements of the structure. The zero position error of the kingpin angle and the error of each wheel location parameters obtained from the test met the requirements of the calibration specification, which verified the feasibility of the device.