The inspection device of a head-up display (HUD) for a vehicle automatically inspects and corrects images projected on a windshield glass of the vehicle by an HUD unit in the vehicle and may include i) a frame where the vehicle is conveyed in-and-out, ii) a moving unit coupled to the frame and reciprocating in the front-and-rear and left-and-right directions of the vehicle, iii) a multi-axis robot mounted on the moving unit and configured to move the vehicle in an up-and-down and back-and-forth direction, iv) a vision camera mounted on an arm of the multi-axis robot and digitally capturing images projected on the windshield glass as vision data, and v) a controller inspects whether the HUD unit operates normally and controls operation of the HUD unit by analyzing the vision data acquired from the vision camera.