Disclosed is a mobile communication system and method for packet hand-over between asynchronous communication network and synchronous communication network, and mobile communication terminal therefor for enabling a mobile phone to be connected with a synchronous network using a call re-sending message transmitted in an asynchronous network. The mobile communication system and method saves the time that a mobile phone, which performs a packet hand-over from an asynchronous network to a synchronous network, re-connects the synchronous network with a packet call, because the call re-sending message transmitted in an asynchronous network is provided to a multi mode multi band mobile phone in case that a hand-over is requested.