To determine the stop time of disaster emergency, the states of emergency were divided into two kinds of states, including emergency tension state and emergency stationary state after analyzing the influence factors of emergency termination states. Firstly, the maximum time N was found out by Markov decision model after the emergency state going into the stable phase, and then the optimal stop theory was used to solve the question of the emergency termination to find the most optimal termination time during the N, finally, the Markov chain's decision model of emergency state termination was established, which could accurately solve the question of the quantification decision of the end time of emergency state, and the calculation was simple. Markov model provided the theory support for emergency termination decision.