The present application relates to a method for establishing a connection, and a terminal device. The method comprises: a relay terminal accepts a communication connection initiated by a remote terminal; the relay terminal establishes a protocol data unit (PDU) session with a network device, the PDU session being used for relaying data of the remote terminal; the relay terminal processes the PDU session according to service description information; and the relay terminal sends information of the remote terminal to the network device according to the processed PDU session. By means of the embodiments of the present application, the process of the remote terminal accessing a network can be optimized.