The present invention relates to a cyber train ticket sales system using a short message service (SMS), in which a user can purchase train tickets for changing trains while traveling in a train thereby conveniently traveling by train. The present invention provides a cyber train ticket sales system, including a client connectible to the Internet and a sales server for selling a train ticket to the client, wherein the sales server comprises a seat management module for providing a connected client with seat status by a train type in real-time; a ticket sales module for registering information on a purchaser, information on a selected ticket, and a phone number, and issuing a cyber train ticket if the client requests purchase of the train tickets; a payment module for providing the client with a payment means for making a payment for the cyber train ticket in connection with the ticket sales module, and storing and managing payment details; an SMS management module for transmitting the issued cyber train ticket to the phone number registered when the cyber train ticket is purchased through SMS if the payment is made; a transfer-to-crew module for providing the issuance information to a target train of the issued cyber train ticket if the cyber train ticket is issued; and a control module for controlling data flow between the modules.