A flow rate measuring device for measuring and recording an amount of gas consumed by a respective of gas appliances (31, 32, 33), comprising: a flow rate storage unit having a fixed flow rate storage unit in which an amount of gas consumed by a respective of identified gas appliances is storable and an unfixed flow rate storage unit in which an amount of gas consumed by at least one unidentified gas appliance is storable; a determining unit configured to detect an activation and a stop of the respective of gas appliances based on a differential value of a gas flow rate measured; a first appliance identifying unit responsive to a detection of activation by the determining unit to identify an activated gas appliance based on a gas consumption profile exhibited by the gas appliance during the activation; a second appliance identifying unit responsive to a detection of a stop by the determining unit, after a plurality of gas appliances are respectively identified simultaneously in use by the first appliance identifying unit, to monitor a gas flow rate measured subsequent to the detection of a stop in search of a gas consumption profile discerned from the measured gas flow rate which is attributable to one among the plurality of gas appliances and identify a stopped gas appliance and/or gas appliance still being in use among the plurality of gas appliances; and a control unit; characterized by an appliance flow rate integrating unit configured to calculate, and store in the fixed flow rate storage unit, an amount of gas consumed by each of the plurality of gas appliances from an activation thereof till the detection of a stop by the determining unit and also calculate, and store in the unfixed flow rate storage unit, an amount of gas consumed after the detection of a stop by the determining unit for which no corresponding gas appliance could be determined at the time of the detection of a stop; and the control unit being configured to add the amount of gas consumed after the detection of a stop and stored in the unfixed flow rate storage unit to the gas amount of the corresponding appliance identified by the second appliance identifying unit and stored in the fixed flow rate storage unit once the corresponding appliance can be determined. a flow rate storage unit having a fixed flow rate storage unit in which an amount of gas consumed by a respective of identified gas appliances is storable and an unfixed flow rate storage unit in which an amount of gas consumed by at least one unidentified gas appliance is storable; a determining unit configured to detect an activation and a stop of the respective of gas appliances based on a differential value of a gas flow rate measured; a first appliance identifying unit responsive to a detection of activation by the determining unit to identify an activated gas appliance based on a gas consumption profile exhibited by the gas appliance during the activation; a second appliance identifying unit responsive to a detection of a stop by the determining unit, after a plurality of gas appliances are respectively identified simultaneously in use by the first appliance identifying unit, to monitor a gas flow rate measured subsequent to the detection of a stop in search of a gas consumption profile discerned from the measured gas flow rate which is attributable to one among the plurality of gas appliances and identify a stopped gas appliance and/or gas appliance still being in use among the plurality of gas appliances; and a control unit; characterized by an appliance flow rate integrating unit configured to calculate, and store in the fixed flow rate storage unit, an amount of gas consumed by each of the plurality of gas appliances from an activation thereof till the detection of a stop by the determining unit and also calculate, and store in the unfixed flow rate storage unit, an amount of gas consumed after the detection of a stop by the determining unit for which no corresponding gas appliance could be determined at the time of the detection of a stop; and the control unit being configured to add the amount of gas consumed after the detection of a stop and stored in the unfixed flow rate storage unit to the gas amount of the corresponding appliance identified by the second appliance identifying unit and stored in the fixed flow rate storage unit once the corresponding appliance can be determined.