To perform production control and facility maintenance at low cost without requiring any dedicated communication means.

A client side is equipped with a storage device 11 for storing a control program for a robot, a main arithmetic unit 12 which analyzes and performs the control program stored in the storage device, and an interface device 13 which makes a connection with an external infrastructure, and the interface device 13 sends and receives electronic mail to and from a host side, so that the robot 20 can be controlled. Consequently, no dedicated communication means is needed by sending and receiving the electronic mail through the network infrastructure like the Internet and the production control and facility maintenance can be carried out at low cost, so that the superior industrial robot can be actualized.