A bandwidth control server, a bandwidth control program recorded on a computer readable record medium, and a monitoring system that control the sending of image data obtained by cameras in accordance with priority corresponding to a situation. A setting information storage section stores setting information regarding a camera installed at each point. When disaster information is acquired, a disaster detection section extracts a disaster type and a disaster area from the disaster information. A priority determination section searches the setting information on the basis of the disaster type and the disaster area and extracts setting information corresponding to the disaster type. Then the priority determination section determines priority for sending image data obtained by cameras installed in the disaster area on the basis of the extracted setting information. A bandwidth control section ensures bandwidths which can be used for sending the image data in descending order of the priority on the basis of the priority and bandwidth information acquired by a network monitoring section.