An image forming apparatus that is an authenticating apparatus includes an authentication-processing unit, a display area, a display-control unit and a re-entry-processing unit. The authentication-processing unit executes user authentication by comparing an entered password with a set password. The display area displays an entire entered password so as to be visible when non-matching characters are included in the entered password. The display-control unit causes a re-entry screen on which an input field is arranged in which correction characters are entered to be displayed. The re-entry-processing unit corrects the non-matching characters of the entered password based on correction characters that are entered in the input field. The authentication-processing unit compares the entered password that is corrected by the re-entry-processing unit with the set password.