To transmit video data of an image pickup device to a monitor terminal with satisfactory response, without degrading quality and to display the data thereon, even when a transmission capacity of a communication network interconnecting the image pickup device and the monitor terminal is insufficient.

A video server device 30 is provided in a monitor center 7 and camera controllers 2a', 2b', etc., transmit tentatively video data photographed by cameras 1a, 1b, etc., to the video server device 30 via an ISDN 4, in response to video image distribution request from each of monitor terminals 20a, 20b, etc. The video server device 30 that tentatively stores or saves the data distributes the data to the monitor terminals 20a, 20b, etc., that are request sources.