The present invention relates to an apparatus and method for inputting a password using a game. The method includes displaying, on a display unit, a password image corresponding to at least one password information, displaying, on the display unit, at least one obstacle image, displaying, on the display unit, a character image moved based on movement information received from an external input unit, determining whether the character image is in contact with the password image, and controlling a user authentication procedure to be performed based on the at least one password information corresponding to the password image when the character image is in contact with the password image.