1. A network discovery and selection supporting method in an operation method of a network node for supporting network discovery and selection of a user equipment (UE) in a wireless communication system, the network discovery and selection supporting method comprising: receiving, from the UE, a network discovery and selection (NDS) rule request message requesting an NDS rule; transmitting, to at least another network node, a policy request message requesting NDS rule generation support information for generating the NDS rule; receiving, from the at least another network node, a policy response message including the NDS rule generation support information; generating an NDS rule based on the NDS rule request message and the policy response message; and transmitting, to the UE, an NDS rule response message including the generated NDS rule, wherein the NDS rule includes information regarding networks available to be discovered and selected by the UE and priority information of the networks, and wherein at least some of the networks have different radio access technology (RAT) types.