The utility model relates to a fixing structure for an acceleration sensor, and the fixing structure is used for fixing the acceleration sensor onto an outer box wall of a transformer. The fixing structure comprises a base, wherein one side of the base is bonded to the outer box wall of the transformer, and the other side of the base is connected with the acceleration sensor by screws. Compared with the prior art, the fixing structure for the acceleration sensor provides a noninvasive, convenient and accurate measuring method for the collection of mechanical vibration signals of a transformer on-load voltage regulation switch, such that the outer box wall of the transformer is not damaged, and the mechanical vibration signal collection position is kept constant, thereby facilitating the comparison of measurements and improving the reliability of vibration signal comparison; and based on the fixing structure, the problems of field mounting of the acceleration sensor and the comparison reliability of mechanical vibration signals repeatedly collected from a same on-load voltage regulation switch are solved.