Abstract: With the development of power grid scale, the scale of equipment and data continues to develop, which will inevitably lead to increasingly complex data manipulation for short-circuit current calculations and highlight the drawbacks of the traditional calculation model, which is heavy and error-prone. NET operating platform, the auxiliary calculation software for branch short-circuit current of 500 kV transformer has been developed. The auxiliary calculation software adopts MVC framework, which can batch calculate and analyze the short-circuit current of transformer branch. Firstly, edit the bus name set and other basic data. Secondly, batch calculate the single-phase and three-phase short-circuit current of the medium voltage side and high-voltage side of the 500 kV transformer. Thirdly, output the analysis report of the results. The application results show that the transformer branch short-circuit current auxiliary calculation software fully applies the advantages of existing calculation software and the MVC frame framework to improve the calculation efficiency and avoid human errors.