A gas measuring device for a secondary battery, according to the present invention, comprises: a chamber for accommodating the secondary battery therein; a heater unit for igniting the secondary battery accommodated in the chamber by applying heat to the chamber; a collecting pipe connected to the inside of the chamber so as to collect gas generated from the secondary battery; a vacuum unit connected to the collecting pipe so as to vacuumize the inside of the chamber and allow the gas to enter the collecting pipe; and a gas measuring unit for measuring the gas having entered the collecting pipe.