A state transition method, applied to an access network device, wherein a relay terminal is connected to the access network device, the relay terminal is connected to at least one communication terminal, and the at least one communication terminal is connected to the access network device through the relay terminal, the method comprising: controlling the at least one communication terminal to leave a connection management connected, CM-connected, state with the access network device; determining that each of the at least one communication terminal connected to the access network device through the relay terminal has left the CM-connected state with the access network device and sending a first control message to the relay terminal, wherein the first control message is used for instructing the relay terminal to leave a CM-connected state with the access network device; wherein the controlling the at least one communication terminal to leave the CM-connected state with the access network device comprises one of the following: sending a wireless connection releasing message to the at least one communication terminal, wherein the wireless connection releasing message is used for instructing the at least one communication terminal to transition to a connection management idle, CM-idle, state; and sending a second wireless connection suspension message to the at least one communication terminal, wherein the second wireless connection suspension message is used for instructing the at least one communication terminal to transition to a radio resource control inactive state. controlling the at least one communication terminal to leave a connection management connected, CM-connected, state with the access network device; determining that each of the at least one communication terminal connected to the access network device through the relay terminal has left the CM-connected state with the access network device and sending a first control message to the relay terminal, wherein the first control message is used for instructing the relay terminal to leave a CM-connected state with the access network device; wherein the controlling the at least one communication terminal to leave the CM-connected state with the access network device comprises one of the following: sending a wireless connection releasing message to the at least one communication terminal, wherein the wireless connection releasing message is used for instructing the at least one communication terminal to transition to a connection management idle, CM-idle, state; and sending a second wireless connection suspension message to the at least one communication terminal, wherein the second wireless connection suspension message is used for instructing the at least one communication terminal to transition to a radio resource control inactive state. sending a wireless connection releasing message to the at least one communication terminal, wherein the wireless connection releasing message is used for instructing the at least one communication terminal to transition to a connection management idle, CM-idle, state; and sending a second wireless connection suspension message to the at least one communication terminal, wherein the second wireless connection suspension message is used for instructing the at least one communication terminal to transition to a radio resource control inactive state.