Disclosed is a method, apparatus and system for providing a financial service through a mobile station in a mobile communication network. The system includes the mobile station for reading a barcode, transmitting user authentication data and the barcode, receiving passbook data, and storing and managing the passbook data; the mobile communication network for receiving the user authentication data and the barcode to thereby provide barcode information to a bank server, determining whether to approve the service; the bank server for managing the passbook data, allocating a specific barcode to each automatic machine, providing the location information of the automatic machine, corresponding to the barcode, and providing the mobile station with a banking service; and the automatic machine for receiving the barcode and outputting the received barcode, and providing the banking service through the bank server when the service is approved.