The utility model discloses a secure transportation device for low-concentration methane gas, which is composed of a water-sealed fire-resisting explosion-venting device and an automatic explosion-resisting device. The automatic explosion-resisting device is composed of an explosion-resisting valve, an explosion-venting device, a controller and a sensor, wherein, the sensor and the explosion-resisting valve are connected with the controller through leads, the gas outlet pipe of the water-sealed fire-resisting explosion-venting device is connected with the gas exhaust pipe thereof, and the gas inlet pipe of the water-sealed fire-resisting explosion-venting device is communicated with the gas exhaust pipe of the explosion-resisting valve, and the explosion-venting device which is communicated with the pipeline is arranged on the pipeline near the explosion-resisting valve; the sensor is composed of a flame sensor and/or a pressure sensor which is arranged on the gas exhaust pipe above. The utility model is beneficial for changing the low-concentration methane gas into valuable gas and can reduce the environment pollution caused by the methane gas exhaust; in addition, the transportation device has simple structure and can be popularized conveniently.