The invention discloses a power transformer. The power transformer comprises a transformer body, a mounting base, lug plates, fastening bolts, locking nuts, positioning grooves, supporting bases, circulating fans, ventilation channels, a support rod, locking rocker arms, support columns, rocking handles, stand column telescopic rods, bases, a clamping ring, a pull rod, a pull rod clamping sleeve,positioning supports, positioning support clamping sleeves, locking knobs and a vertical rod. Accordingly, the transformer can be installed according to the actual installation environment, the transformer can be installed conveniently and rapidly under various environments, and the installation steps of operators in the transformer installation process are simplified; meanwhile, on one hand, thetransformer construction quality is improved, and the construction cost of the transformer loading and unloading operation is lowered; on the other hand, the construction efficiency of the transformerloading and unloading operation is greatly improved, the high practicability is achieved, the operation effect is guaranteed, the power transformer is suitable for various different installation modes, the stability and precision are high, and use of manpower is effectively reduced.