A multifunctional test system for car body safety comprises a test bed, a loading control system and a data acquisition and processing system. deformation vectors are measured accurately through an image three-dimensional measuring method, three large devices are replaced, the strength and the rigidity of key parts of side doors, the car roof, bumpers and the like are tested, and the whole test process is collected, represented, analyzed and evaluated. The test bed is applicable to test of passenger cars of various types, and displacement control, loading force control and logical control methods are provided. Side door and bumper tests can be performed when the interchangeable loading device is a column loading device, and the car roof test can be performed through a car body location device when the interchangeable loading device is changed into a plate type loading device. Distribution of yield points can be determined through an infrared thermogram, and the static position before and after the test of the datum point and interpolation moving positions of deformation points can be obtained by arranging laser measurement points. By means of the system, accurate boundary conditions are provided for calculation of theories of finite elements and the like.