A gas shutoff device (100, 110) comprising: a flow rate measurement unit configured to measure a flow rate of gas flowing through a flow path; an appliance determination unit configured to determine a gas appliance in use based on the flow rate of gas measured by the flow rate measurement unit; a shutoff valve configured to shut off the flow path; a wireless communication unit configured to regularly perform wireless communication with an outside; and a communication interval setting unit configured to set a communication interval that is an interval in the wireless communication of the wireless communication unit, wherein the communication interval setting unit is configured to set the communication interval according to the gas appliance in use determined by the appliance determination unit, characterized in that the communication interval setting unit is configured to set the communication interval to a first predetermined interval when the appliance determination unit determines that no gas appliance is used, and the communication interval setting unit is configured to set the communication interval to an interval shorter than the first predetermined interval when (i) the appliance determination unit determines that the gas appliance in use is a stove, and (ii-1) gas at a first predetermined flow rate or more is continuously used by the gas appliance in use for a first predetermined time or more, or (ii-2) gas at a flow rate less than the first predetermined flow rate is continuously used by the gas appliance in use for a second predetermined time or more, the second predetermined time being set longer than the first predetermined time. a flow rate measurement unit configured to measure a flow rate of gas flowing through a flow path; an appliance determination unit configured to determine a gas appliance in use based on the flow rate of gas measured by the flow rate measurement unit; a shutoff valve configured to shut off the flow path; a wireless communication unit configured to regularly perform wireless communication with an outside; and a communication interval setting unit configured to set a communication interval that is an interval in the wireless communication of the wireless communication unit, wherein the communication interval setting unit is configured to set the communication interval according to the gas appliance in use determined by the appliance determination unit, characterized in that the communication interval setting unit is configured to set the communication interval to a first predetermined interval when the appliance determination unit determines that no gas appliance is used, and the communication interval setting unit is configured to set the communication interval to an interval shorter than the first predetermined interval when (i) the appliance determination unit determines that the gas appliance in use is a stove, and (ii-1) gas at a first predetermined flow rate or more is continuously used by the gas appliance in use for a first predetermined time or more, or (ii-2) gas at a flow rate less than the first predetermined flow rate is continuously used by the gas appliance in use for a second predetermined time or more, the second predetermined time being set longer than the first predetermined time.