Aiming at the complex and timeconsuming problem of the existing threephase power flow calculation method for distribution network, a hybrid power flow model based on πtype interfaces is proposed in this paper. In the hybrid model, a threephase model for threephase asymmetrical network, and a singlephase model for threephase symmetrical network are considered separately. Then, the hybrid power flow model is established by connecting the two parts of network through a πtype equivalent interface. In addition, the node admittance matrix, the node power injection equation of the interface and its influence on Jacobian matrix are obtained.The correctness and superiority of the proposed model is verified by comparing the calculation accuracy and speed of the proposed model and the full threephase power flow model under different threephase unbalance conditions based on IEEE standard example.