A method of sharing credential in a wireless communication system comprising a first user equipment, a second communication device and a network, includes transmitting a temporal credential and a credential custody request, from the first communication device, to the network; transmitting first custody information, by the network, to the first communication device; transmitting a credential acquiring request and second custody information, by the second communication device, to the network; and determining whether to transmit the temporal credential to the second communication device according to the second custody information.