Abstract: Disclosed relat to a password input apparatus that prevents the exposure of password to strangers while the user inputs the password, furthermore, prevents strangers from perceiving the password easily through distinctions of specific keys corresponding to the password due to repeated use. According to the invention, a series of password data (random digit string) are displayed on display elements (33) and the password data displayed are selected using selection keys (40) by a user. Here, the arrangement of the password data is varied every time when the user inputs the password. A display window (32), having a predetermined height, provided on the top of the display element (33), can narrow the angle of view against the light emitted from the display elements (33), thus preventing strangers other then the users standing in a straight line against the display element (33) from perceiving the passwordk easily.