The present invention relates to a safety device for tillers and, specifically, to a safety device for tillers, which lessens impact when an overload is caused by an obstacle such as a stone or rock during the farming of a farmland by means of a tiller, such as a tractor plow, twin bottom plow, furrow plow, hiller, and pan-breaker, so as to prevent damage to the tiller and improve work efficiency, and can be manufactured using a very simple structure. To this end, the present invention provides a safety device for a tiller comprising: a main frame including a tractor connection part provided at the front side thereof to be connected to and towed by a tractor； a tilling part vertically rotatably installed on the main frame to till soil； and a cylinder for elastically supporting the tilling part rotating on the main frame, wherein the cylinder comprises: a body into which a rod is inserted through one side thereof； an inner cylinder which is inserted in the body to be at the one side of the body, is formed to be shorter than the movement range of a compressing plate formed at the end of the rod, and is formed to have an outer diameter smaller than the inner diameter of the body to form a space therebetween； a communicating hole which is formed through the inner cylinder to allow the space and the inside of the inner cylinder to communicate with each other therethrough and is formed to be behind the compressing plate when the rod is maximally extended； a valve for opening/closing the communicating hole； and an opening/closing part disposed behind the compressing plate to open/close the valve by forward and backward movements of the compressing plate, wherein the compressing plate is configured to have an outer diameter allowing insertion thereof into the inner cylinder.La présente invention concerne un dispositif de sécurité pour sarcleuses et, spécifiquement, un dispositif de sécurité pour sarcleuses, qui réduit l'impact lorsqu'une surcharge est provoquée par un obsta
