In order to reduce the operation loss of ISOP-DAB converter with the same parameters of each module, a hybrid optimization control strategy based on double phase shifting is proposed. First, an inner and outer phase-shift ratio coefficient \(\theta\) is introduced to ensure that the converter operates in a state where the inner phase-shift ratio is smaller than the outer phase-shift ratio to prevent a large increase in its current stress and backflow power. The idea of weighting method is used to establish the index function for current stress and backflow power, and construct the single-module co-optimization model. Second, the power transfer characteristics of ISOP-DAB converter are analyzed, and the direct power control method is used to achieve power equalization and combine with the proposed single-module co-optimization model to construct a hybrid optimization control strategy for ISOP-DAB converter. Finally, the effectiveness of the control strategy is verified by building a MATLAB/Simulink simulation platform and running the real machine.