The invention discloses an application deployment method in a mobile edge cloud, and the method combines fog computing with a mobile edge cloud network, and constructs a three-layer tree edge network structure consisting of a remote radio unit (RRU), a baseband processing unit (BBU) and a central controller. On the basis, an application deployment problem in the mobile edge cloud is converted into a binary integer programming problem, and an application deployment method for solving the problem is provided. According to the method, a descending optimal adaptation algorithm (BFD algorithm) is combined with a PRA algorithm, an application deployment mode capable of reducing the total cost is found, and the application is reasonably deployed in an edge server. In the aspect of the redeployment frequency of the application program, a heuristic redeployment method is provided, and the method utilizes a hit rate monitoring function to heuristic trigger redeployment operation, so that the system can reasonably determine the redeployment frequency, and meets the time-varying requirement.