Abstract: An online reliability evaluation method for distribution network considering time sequential load transfer procedure is presented in this paper. The method, which takes the medium voltage distribution feeder as the evaluation object, assesses the worst outage risk in real time under the extreme fault condition. In order to simulate the load restoration procedure after fault, an optimization model of the load transfer strategy is set up aiming at minimizing total energy loss. The power variation in load transfer periods as well as the continuous back-up power supply ability is considered in the model, and a multi period heuristic search algorithm is applied to solve it efficiently. The effectiveness and feasibility of the proposed method is verified by case study, and the results can provide references for dispatching operators in distribution network.