When distributed generations are connected into distribution network, it will bring about many problems in traditional distribution network, such as protective relays refusing to operate, mal-operation, de-sensitivity, etc. Therefore, an improved protection scheme adapt to mass DG access to distribution network is put forward. From the perspective of DG connecting location and capacity, the impact of connected bus and feeder on traditional three-stage current protection and inverse-time over-current protection is analyzed, and the allowed accessing capacity of three-stage current protection is calculated. Verse-time over-current protection based on low voltage acceleration and a few directional components are configured to meet the protection requirements of the distribution network with mass DG. A 10 kV distribution system with DG is simulated and analyzed by PSCAD/EMTDC. Simulation results show that the improved method can meet protection requirements of distribution network with different capacity DG access, has good economy and practicality, and confirms to the development status of current distribution network.