A communication method, applied to a first user equipment in a device to device communication system, wherein the method comprises: receiving (201, 202), in a paging period of the first user equipment or a third user equipment, a first message from a base station, wherein the first message comprises a service priority of the third user equipment and instructs to page the third user equipment to communicate with the base station and the base station serves the first user equipment; sending (204a, 204b, 205a, 205b), based on the service priority of the third user equipment, a second message to the third user equipment in a device to device connection between the first user equipment and the third user equipment, wherein the second message instructs the third user equipment to access the base station or to communicate with the base station through a relay serving of the first user equipment, wherein the sending (204a, 204b, 205a, 205b) the second message to the third user equipment based on the service priority of the third user equipment includes: sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a first priority, where the second message is used to instruct the third user equipment to access the base station; or sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a second priority, where the second message is used to instruct the third user equipment to perform communication with the first user equipment, and the first priority is higher than the second priority, wherein after receiving the first message sent by the base station, the first user equipment selects, according to the service priority of the third user equipment, whether to provide the relay serving for the third user equipment or to instruct the third user equipment to access the base station so that for a service of a low service priority, the first user equipment directly provides the relay serving for the third user equipment. receiving (201, 202), in a paging period of the first user equipment or a third user equipment, a first message from a base station, wherein the first message comprises a service priority of the third user equipment and instructs to page the third user equipment to communicate with the base station and the base station serves the first user equipment; sending (204a, 204b, 205a, 205b), based on the service priority of the third user equipment, a second message to the third user equipment in a device to device connection between the first user equipment and the third user equipment, wherein the second message instructs the third user equipment to access the base station or to communicate with the base station through a relay serving of the first user equipment, wherein the sending (204a, 204b, 205a, 205b) the second message to the third user equipment based on the service priority of the third user equipment includes: sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a first priority, where the second message is used to instruct the third user equipment to access the base station; or sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a second priority, where the second message is used to instruct the third user equipment to perform communication with the first user equipment, and the first priority is higher than the second priority, wherein after receiving the first message sent by the base station, the first user equipment selects, according to the service priority of the third user equipment, whether to provide the relay serving for the third user equipment or to instruct the third user equipment to access the base station so that for a service of a low service priority, the first user equipment directly provides the relay serving for the third user equipment. sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a first priority, where the second message is used to instruct the third user equipment to access the base station; or sending the second message to the third user equipment when the first message is used to page the third user equipment if the service priority of the third user equipment is a second priority, where the second message is used to instruct the third user equipment to perform communication with the first user equipment, and the first priority is higher than the second priority, wherein after receiving the first message sent by the base station, the first user equipment selects, according to the service priority of the third user equipment, whether to provide the relay serving for the third user equipment or to instruct the third user equipment to access the base station so that for a service of a low service priority, the first user equipment directly provides the relay serving for the third user equipment.