A monitoring system comprises an equipment management device, a relay server, and monitoring terminals. The equipment management device is configured to establish with the relay server first communication for notifying the monitoring terminals of the states of equipment items. Furthermore, the equipment management device is configured to establish with the relay server second communication, which is different from the first communication, for monitoring equipment information regarding the equipment items from each of the monitoring terminals. The monitoring terminals establish the first communication and second communication with the relay server. The relay server is configured to relay the first communication and second communication.