A communication volume control device according to an aspect of the present disclosure includes: at least one memory configured to store instructions; and at least one processor configured to execute the instructions to: acquire, when a disaster occurs, target area information indicating a target area expected to be impacted by the disaster that has occurred; and instruct a plurality of imaging devices, which are mounted to each of a plurality of moving bodies and which transmit monitoring information related to captured images to a monitoring device at a predetermined timing, to adjust a communication volume based on the target area information when transmitting the monitoring information to the monitoring device from the imaging devices.