Aircraft landing with low fuel usually is caused by alternate landing changing in the air. Aiming at the problem of collective alternate landings of multiple flights in the area.Select the most complex situation,that is, when dangerous weather in the route or terminal area. The basic conditions of the fly limit zone under dangerous weather are obtained by combining meteorological data and historical tracks; Use A * and improved gray wolf Dijkstra methods to plan the diversion path for two different ways to the alternate aerodrome: maneuver flight and flight along the route. Firstly, taking the shortest total flight time of alternate flight as the single objective, and then integrating the expectations of flight, control, airport and airline, a multi-objective function is constructed, the dynamic decision-making time interval is defined, and a dynamic optimization scheme of multi flight alternate in the region based on single objective and multi-objective is proposed; Using the "8.12" North China large area alternate landing data, the total flight time obtained by selecting the direct flight A * algorithm is reduced by 100 and 62 min respectively, and the total flight time obtained by the improved gray wolf Dijkstra algorithm according to the route is reduced by 73 and 14 min; Moreover, in the multi-objective scheme, the overall time of flight resumption to the original destination is 63 min earlier, and the total cost is reduced by 62900 yuan. The above shows that the scheme can take into account the needs of multiple parties and improve the economy on the basis of ensuring the safety of flight alternate landing.