In an X-ray inspection apparatus, an X-ray detector starts to acquire an X-ray image before a motor is started and outputs a periodic acquisition timing signal of the X-ray image, a generation circuit control unit generates a motor start signal based on a first signal generated from the acquisition timing signal, and a start signal generation circuit generates and outputs a controller start signal to a controller at an output timing of the acquisition timing signal after receiving the motor start signal. A CT image is generated based on a plurality of the X-ray images that are acquired after a rotation speed of the motor reaches a fixed speed.