In order to solve the problem of cross-subsidy transfer arising in the process of slow opening of the electricity market in market-based trading, firstly, a theoretical transmission and distribution tariff measurement model for different user types at different voltage levels is constructed, secondly, the scale of transfer cross-subsidy after each type of user participates in market-based trading is measured using the price difference method, and a transfer cross-subsidy balance model for the semi-open electricity market environment is constructed, and finally, the 2019 electricity data of China’s province S is used as an example to verify the feasibility and superiority of the model. The results show that the proposed equilibrium model can effectively mitigate the transfer cross-subsidy problem within the electricity market when the increase of the market-based trading degree in province S does not exceed 21%, and it can also provide ideas to mitigate the regional transfer cross-subsidy problem in China.