A network out-of-synchronization state processing method and apparatus, and a network access method and apparatus are provided. The method includes: if a first network device does not receive, in a first time length after the first network device determines that a terminal is in a network out-of-synchronization state, a measurement message reported by a second network device in a signal coverage area of the first network device, instructing at least one second network device in the signal coverage area of the first network device to send paging signaling to the terminal; and setting a network status of the terminal to a detached state if the first network device determines that in a second time length, no second network device in the signal coverage area of the first network device receives a paging response sent by the terminal, and that the terminal is still in the network out-of-synchronization state.