Instance switching method and relevant device

The embodiment of the application discloses an instance switching method. The instance switching method comprises the following steps that: when target user equipment (UE) moves into the cell range ofa second base station, and before the target UE successfully accesses the second base station, a first switching device determines that a first instance on a first mobile edge cloud (MEC) platform for providing a target application service for the target UE is to be switched to a second instance on a second MEC platform; before the target UE successfully accesses the second base station, the first switching device informs the first MEC platform that the first instance for providing the target application service for the target UE is to be switched to the second instance; and when the target UE fails in accessing the second base station, the first MEC platform acquires that the instance for providing the target application service for the target UE is to be switched to the second instanceon the second instance on