Disclosed is a method for managing a duplicated MMS arrival notification message. The method includes the steps of receiving, by the MMS proxy server, a download completion notification message transmitted from the receiving mobile terminal and transmitting a duplicated-message deletion message to the receiving mobile terminal in response to the download completion notification message, receiving, by the receiving mobile terminal, the duplicated-message deletion message and deleting a relevant message from among received MMS arrival notifications, and displaying that the relevant message has been deleted in an MMS server and thus cannot be download for the user.