The disclosure relates to a wireless self-powered gas sensor based on electromagnetic oscillations triggered by external forces and its fabrication method. The sensor includes a gas test chamber, a first friction layer, a second friction layer, an interdigital electrode, a gas-sensitive material, an air inlet, an air outlet and leads. The gas sensor of the disclosure is an integrated detection system of “environmental energy collection—wireless energy transmission—active spontaneous detection” that can be driven simultaneously only by external mechanical movement, and can work independently without external power supply. The first friction layer and the second friction layer are arranged outside the gas test chamber. The frictional motion will not interfere with the flow field of the test chamber and the gas molecule absorption and desorption, which ensures the stability of gas detection to the greatest extent.