The invention provides an arc extinguishing chamber of a high-voltage alternating-current filter group circuit breaker. The structure is reasonable, the design is clever, a mechanical structure intensity and an electric field requirement during usage are satisfied, a rekindling rate is low and reliability is high. The arc extinguishing chamber comprises a casing pipe, a static contact device and amoving contact device, wherein the static contact device and the moving contact device are arranged in the casing pipe. Two ends of the casing pipe are provided with sealing flanges respectively. A SF6 gas is filled in a sleeve. The static contact device comprises a static main contact and a static arc contact. The moving contact device comprises a middle contact, a piston, an air cylinder, a moving main contact, a moving contact seat fixedly connected to a free end of the air cylinder, a nozzle seat fixedly arranged on an end portion of the moving contact seat, a moving arc contact, a pistonrod and a nozzle fixedly arranged in an inner side of the nozzle seat. A piston is arranged in the middle contact. The piston rod coaxially passes through the piston. The moving contact seat is provided with an inclined channel connecting an air cylinder air chamber and a nozzle inner cavity. When the arc extinguishing chamber is closed, the static main contact and the moving main contact form clearance fit, and the static arc contact and the moving arc contact are contacted and cooperated.