The present disclosure relates to a gas and earthquake detector, a gas and earthquake remote monitoring system using the same and a method thereof, and more particularly, to a gas and earthquake detector, a gas and earthquake remote monitoring system using the same and a method thereof, which detect a plurality of gases and earthquakes, detect and autonomously warn gas leakage of a plurality of detection target devices sensitive to the gas and the earthquake, and the earthquake around the detection target device, and easily register the gas leakage and the earthquake in a remote management means through a user mobile terminal of a user to monitor the gas leakage of the detection target device and the earthquake at a detection target device location through the remote management means.