The invention relates to a supersonic nozzle which consists of a ring-shaped shrinking-expanding nozzle, an injected charging pipe, an accelerating pipe and a target head, wherein supersonic gas flow of the ring-shaped shrinking-expanding nozzle is used for injecting and accelerating low-speed gas flow of a central charging circular pipe to an supersonic state, so that material particles obtain enough dynamic energy along with the gas flow, and can be gathered at the gas flow center to crash the fixed target head at the downstream in a focused mode, and therefore, the problems such as difficult charging, low material particle dynamic energy and low collision reaction efficiency in high-speed gas flow solid-phase reaction are solved.