GAS SUPPLY SYSTEM

A tank (11) of a gas supply system (10) is configured to be detachably attached to a gas consumption device (20). A control device (50) is configured to, when the tank (11) is detached, close an open/close valve (15) to stop supply of gas from the tank (11), stop consumption of gas by the gas consumption device (20) after the gas in the supply channel (22) is consumed, and perform computation to permit detachment of the tank (11) after confirming that pressure acquired from a pressure sensor (31) is not rising to a predetermined level or higher.