A network system for recovering from a link failure in a Voice over Internet Protocol (VoIP) service comprises: a first media gateway having a current link setting and transmitting a corresponding packet upwardly for the VoIP service; a second media gateway which is link-connected to the same remote terminal as the first media gateway for the VoIP service; a media gateway controller for allocating the second media gateway for link resetting, and for transmitting allocation information when receiving failure information of a link set through the first media gateway; and a router for determining whether a packet transmitted from the first media gateway is received within a set time to determine whether there is a failure of the set link, for transmitting the link failure information to the media gateway controller, and for resetting the link to the second media gateway according to the allocation information transmitted from the media gateway controller when there is a link failure. A method for recovering from a link failure in a VoIP serviced comprises steps corresponding to the aforementioned functions.