Abstract: Energy internet is an effective way to achieve large-scale use of renewable energy source, which has tremendous potential. In this paper, the research statuses of the energy internet and DC distribution were introduced; on this basis, the typical topology of AC energy internet was described and analyzed. Then, the energy internet based on flexible medium-voltage DC distribution was presented, and the topology and key technologies were discussed; taking a park in Shenzhen as an example, the application scheme of energy internet based on flexible medium-voltage DC distribution was analyzed. At last, the development prospect of DC energy internet was forecasted.