The access of Distributed generation (DG) will lead to the change of power flow and loss of distribution network. In order to fully understand the impact of distributed generation on distribution network loss and realize the reasonable allocation of distribution network loss, the concept of loss contribution rate of DG to distribution network is introduced, and based on this, a loss allocation method considering the loss contribution rate of DG is proposed in this paper. Firstly, a set of impact power indicator system of DG to distribution network loss is designed, which includes the basic property index sub-system and the run property index sub-system. The basic property index sub-system covers the basic parameters of the DG, such as the capacity and grid location. The run property index sub-system covers the operation parameters of the distribution network, such as the annual power supply and network load rate. Next, according to the index property, each index is preprocessed, weights of each index are determined by means of the order relationship method and the entropy weight method (EWM), and the loss contribution rate of each DG to distribution network is calculated. Then, in the light of the principle of “who caused the incremental part of loss, who is responsible for it”, loss of the distribution network including DG is divided into two parts: the initial part of the network loss is allocated to all users of the original distribution network through the power flow tracing, and then the network loss variation is designed to distributed to each DG based on the loss contribution rate. Finally, the distribution network including DG in a certain area is taken as an example to share the distribution network loss. The final allocation result verify the correctness and rationalities of the proposed method.