With the rapid development of Internet of Things technology and the new generation of mobile communication technology, the interaction between electric vehicles and distribution systems has expanded from a single time dimension to time-space multi-dimensional coordination, which significantly affects the power supply reliability of the new power distribution system. Based on this background, the cluster management strategy of large- scale electric vehicles is analyzed, the mathematical representation method of the temporal and spatial schedulable characteristics of electric vehicles in the distribution system is revealed, and the reliability of the distribution system that considers the temporal and spatial schedulable characteristics of electric vehicles assessment method is proposed. In order to verify the effectiveness of the proposed method, based on the improved IEEE-RBTS BUS6 main feeder F4 system, corresponding calculation and analysis are carried out on the reliability of the distribution system considering the time-space schedulable characteristics of electric vehicles before and after the connection and under different discharge capacities of electric vehicles. The calculation and analysis reveal the influence of electric vehicle access on the power supply reliability of the distribution network under the new situation, which can provide effective theoretical support for the reliability improvement of the power distribution system under the electric vehicle access.