To construct a system capable of realizing easy security while reducing the burden of users or a system manager by performing entering and leaving management by authentication of both staff and visitor in an environment having high open property.

A camera 32 with human sensing sensor and an alarm lamp 33 are set at a gate 31 of a room 3, and connected to a server device 1 which performs the entering and leaving management. The server device 1 manages individual authentication information of users, information showing entering and leaving states, and the like. The camera 32 detects a user who enters or leaves the room, takes a picture of his/her appearance, and transmits a telegram message containing the data to the server device 1. The server device 1 authenticates the entering and leaving user on the basis of the telegram message, and outputs an entering permission signal in a case where one or more staffs are present in the room when the visitor enters the room.