The invention discloses a gas outburst sensor based on a sound wave principle and belongs to a gas sensor. The gas outburst sensor comprises a casing, a frontal sound cavity, an ultrasound piezoelectric film, lateral sound cavities, metal films, fixing electrode plates and a lead, wherein the frontal sound cavity is arranged in front of the casing, the lateral sound cavities are arranged on the side of the casing, the ultrasound piezoelectric film is connected in the frontal sound cavity, the metal films and the fixing electrode plates are sequentially connected in the lateral sound cavities, the lead and the ultrasound piezoelectric film are connected at the back of the casing, at the same time, the lead, the metal films and the fixing electrode plates are arranged, the frontal sound cavity and the ultrasound piezoelectric film form an ultrasonic detector, the number of the lateral sound cavities, the metal films and the fixing electrode plates is respectively two, the lateral sound cavities, the metal films and the fixing electrode plates form two low-frequency acoustic detectors, and by the aid of detection of high-frequency sound waves and low-frequency sound waves, sound waves produced by gas jet which is ejected out of seams of coal layers can be analyzed. The gas outburst sensor has the advantages that high-frequency sound wave signals and low-frequency sound wave signals which are ejected out by the high-pressure gas in the coal layers through seams of the coal layers can be detected, and real-time monitoring for mine gas outburst is achieved.