The utility model belongs to the technical field of nuclear power plant electronic gate valve equipment, and particularly relates to a nuclear power plant atmosphere release valve emergency manual starting device. The nuclear power plant atmosphere release valve emergency manual starting device comprises a matching device, a manual ratchet gear device and a dimension loop, wherein the matching device comprises an upper column and a lower column which are the same in diameter; a square hole is formed in the middle of the upper column; a hexagon hole is formed in the middle of the lower column; the upper column is fixedly connected with the lower column; the manual ratchet gear device is a ratchet gear wrench; the inner diameter of the dimension loop is not smaller than the outer diameters of a locking nut and an opening nut. The nuclear power plant atmosphere release valve emergency manual starting device provided by the utility model has the benefits that a valve can be rapidly opened in emergent situations, is simple and convenient to operate and reliable in application property.