A method and system for synchronizing data between a mobile terminal and an Internet phone is provided. The method includes transmitting an Internet Protocol (IP) address request message from a mobile terminal to an Internet phone, transmitting an IP address response message from the Internet phone to the mobile terminal in response to the IP address request message, establishing a connection between the mobile terminal and the Internet phone using the IP address, and performing data synchronization between the mobile terminal and the Internet phone through the connection.