The utility model discloses an accelerator installation adjustment device with a compact structure and pertains to the technical field of irradiation imaging, which comprises a cabin, an accelerator positioned in the cabin, a front collimator, a rear collimator and a shock absorber. The structure us characterized in that the two sides of the bottom of the cabin is arranged with the guide rail in parallel from the front to the rear; each guide rail is provided with a shock absorber; each shock absorber is connected with the accelerator; the accelerator is positioned in the rear of the cabin and the outlet face is just opposite the collimator; the top of the cabin is provided with a movement amplitude and the movement amplitude is connected with a collimator arranged between the accelerator and the rear collimator. In overhaul, the movement amplitude can send the collimator outside the guide rail so that the accelerator can move to and fro along the guide rail. Compared with present technology, the utility model not only reduces the front to rear dimension of the accelerator cabin, but also makes the overhaul convenient, thereby saving the occupation area of the equipment installation and meeting the requirement of installation in certain narrow occasion.