In contrast to the AC distribution network， the DC distribution network has higher power supply capability， lower line losses， better power quality， freedom from reactive compensation， and is suitable for all kinds of power supply（including renewable energy power） and load access， etc. This paper deals with the DC distribution（relative to the AC distribution） characteristics， its advantages and overall concept in detail; puts forward its network topology structure; and summarizes the network planning design， dispatching control， relay protection， key equipment， and other aspects of the research. Finally， it is pointed out that the DC distribution network optimization dispatching， fault diagnosis and location， DC breaker， etc， are problems for further study.