Abstract: Firstly, this paper describes the installation of transformer in 10 kV metering cabinet, and analyzes the development requirements of auxiliary installation device of transformer in 10 kV metering cabinet. Secondly, through the research and development of auxiliary installation device of 10 kV metering cabinet transformer, the side installation of auxiliary metering current transformer and metering voltage transformer is realized at the same time, which solves the problems of inconsistent installation position of transformer in 10 kV metering cabinet, narrow space in the cabinet and low height of some accessories, effectively improves the installation efficiency of transformer, and reduces the injury caused by installers or the occurrence of transformer damage. Finally, the paper introduces the specific application method and effect of the auxiliary installation device of the transformer.