To provide a secret information input system capable of enhancing the effect of preventing leakage of secret information and reducing maintenance costs.

A mobile terminal 1 receives the input of secret information and temporarily stores the secret information. The secret information stored is sent according to the reception of a radio frequency signal sent from a secret information processing apparatus 2. A predetermined period of time is measured since the input of the secret information is received, and after the secret information is sent by means of the radio frequency signal, the secret information stored is deleted. The secret information processing apparatus 2 sends the radio frequency signal and receives the secret information sent from the mobile terminal 1. The processing apparatus performs a predetermined process according to the secret information.