The invention discloses a high power transformation frequency conversion device, which comprises a transformation frequency conversion device body mounted on a power supply cabinet, wherein a groove is formed on one side of the power supply cabinet, a mounting plate is fixedly mounted at the bottom of the transformation frequency conversion device body, and the bottom of the mounting plate is in contact with the inner wall of the bottom of the groove; two symmetrically arranged mounting grooves are formed on the inner wall of the bottom of the groove, positioning plates are movably mounted inthe mounting grooves, and the top of the positioning plates are welded with the bottom of the mounting plate, sliding grooves are formed on the top of the positioning plates, two sliding rods are welded on the inner walls of the two sides of the sliding grooves, and the same sliding plate is slidably mounted on the outer sides of the two sliding rods located in the same sliding groove. The high power transformation frequency conversion device is simple in structure, high in practicability and convenient to mount, the mounting efficiency of the transformation frequency conversion device body isimproved, rectification processing can be performed on the transformation frequency conversion device body, and the use of people is facilitated.