The invention discloses a gas leak detection method for use in a gas leak detection device. The gas leak detection device comprises a frame. A first cavity is arranged on the frame. A second cavity and a sealing member are arranged in the first cavity. The first cavity is also provided internally with a gas analyzer and a valve body assembly. The gas leakage detection device is provided with a first gas circuit and a second gas circuit. The gas leak detection method comprises the steps of opening the second cavity and placing a to-be-detected object into the second cavity; closing the second cavity, and controlling the sealing member to seal the second cavity; controlling the valve body assembly to open the first gas circuit and close the second gas circuit, and extracting gas inside the second cavity until the second cavity is in a vacuum state; and controlling the valve body assembly to close the first gas circuit and open the second gas circuit, and observing the gas analyzer. The double gas circuit of the invention ensures the accuracy of detection, at the same time, a user confirms whether a gas leak occurs by observing the gas analyzer, and the convenience of the gas leak detection is improved.