A composite jet stream lightning protection and arc extinguishing gap device comprises an arc extinguishing device and a protection gap device mounted near an insulator string in parallel. The arc extinguishing device comprises a self arc extinguishing device, a strong airflow arc extinguishing device, a connecting cylinder and an arc striking plate. Arc extinguishing tubes which continuously cross and are connected in a right-angle shape are placed along the inner wall of the self arc extinguishing device. Each arc extinguishing tube is mainly composed of small copper tubes arranged at the two ends, a metal ball arranged in the middle position, and an outer-wall ceramic tube. The strong airflow arc extinguishing device comprises a lightning signal collector and a gas generator with built-in arc extinguishing gas pills. The device is applicable to overhead transmission lines of various voltage grades. Arc can be extinguished by high-speed airflow generated due to explosion of the arc extinguishing gas pills, and can be extinguished after multiple breakpoints of the arc are cut off by the arc extinguishing tubes connected in a spiral and cross mode and the arc is stretched. Therefore, the defect that a traditional arc extinguishing device directly losses the arc extinguishing function after arc extinguishing gas pills run out is overcome.