A communication method in an inter-RAT network, wherein the inter-RAT network comprises a source network of a first RAT and a target network of a second RAT, the method applies to a process in which user equipment, UE, in the source network reselects the target network, and the method comprises: generating, by a source access network device, a temporary priority list, wherein the temporary priority list comprises a frequency of the source network, a frequency of the target network, a priority of the frequency of the source network, and a priority of the frequency of the target network, and the source access network device is a device that enables the UE to access the source network; sending, by the source access network device, the temporary priority list to a target access network device, wherein the target access network device is a device that enables the UE to access the target network; and sending, by the source access network device, the temporary priority list to the UE, wherein before generating the temporary priority list, the method further comprises: detecting, by the source access network device, load of a serving cell, wherein the serving cell is a cell that is of the source network and on which the UE currently camps; when the load of the serving cell is greater than a first load threshold, detecting, by the source access network device, load of the source network; and when the load of the source network is greater than a second load threshold, triggering the step of generating the temporary priority list. generating, by a source access network device, a temporary priority list, wherein the temporary priority list comprises a frequency of the source network, a frequency of the target network, a priority of the frequency of the source network, and a priority of the frequency of the target network, and the source access network device is a device that enables the UE to access the source network; sending, by the source access network device, the temporary priority list to a target access network device, wherein the target access network device is a device that enables the UE to access the target network; and sending, by the source access network device, the temporary priority list to the UE, wherein before generating the temporary priority list, the method further comprises: detecting, by the source access network device, load of a serving cell, wherein the serving cell is a cell that is of the source network and on which the UE currently camps; when the load of the serving cell is greater than a first load threshold, detecting, by the source access network device, load of the source network; and when the load of the source network is greater than a second load threshold, triggering the step of generating the temporary priority list. detecting, by the source access network device, load of a serving cell, wherein the serving cell is a cell that is of the source network and on which the UE currently camps; when the load of the serving cell is greater than a first load threshold, detecting, by the source access network device, load of the source network; and when the load of the source network is greater than a second load threshold, triggering the step of generating the temporary priority list.