Abstract: This paper proposed an optimal dispatch model based on the scenario analysis which considered interruptible load. Scenario analysis can not only reflect the uncertainty in the operation of power system, but also the dispatch decisions which is time-varying. This paper has made a brief summary of the methods of scenario generation, scenario reduction and scenario tree generation. Besides, the operation constraints of interruptible loads were mainly studied, such as the reduction amount, the interrupt duration, the interrupt frequency and the advance notification time. The comparison between interruptible loads and conventional unit shows that the interruptible loads can be treated as virtual power plants. The optimal dispatch model was established and studied in case, and the case study shows that the optimal dispatch model can effectively handle the uncertainty in the system operation.