A method for releasing a context of a user equipment in a non-3GPP access network and a network entity performing the same are disclosed. In a case in which the UE is a unreachable state, a non-3GPP interworking function (N3IWF) may a UE context release request message to an access and mobility management function (AMF), and may perform protocol data unit (PDU) session user plane de-activation between the AMF, a session management function (SMF), and a user plane function (UPF). In addition, the AMF may transmit a UE context release command message to the N3IWF, and the N3IWF may transmit a UE context release complete message to the AMF.