This invention discloses an automatic locking device for snow anti-skid chains. Wherein the snow anti-skid chain comprises a ratchet wheel lock catch and a anti-skid chain; the anti-skid chain is respectively fixed at the buckle and the outer part of the housing aforesaid, and extends towards three directions. The ratchet wheel lock catch is used to make the anti-skid chain to attach to automobile tires firmly and is controlled by pressing two buttons on its lower side, which is different from existing operational actions of braking off and twisting. The pressing action is simple and available for one hand operation. The overall structure is simple and reliable, conforming to use habits of control actions by users.