The invention provides an outrush prevention device for a valve rod of a butterfly valve. The outrush prevention device is characterized by comprising a valve body, a valve rod, a valve handle, a check ring for hole and a pair of split rings. The valve body is provided with a valve rod shaft hole, and the portion, close the opening, of the upper end of the valve rod shaft hole is provided with an arrangement cavity; the valve rod is inserted into the valve rod shaft hole, the valve handle is installed at the top end of the valve rod, and the spit rings are fixed to the section, located at the cavity bottom end, of the valve rod; the check ring for hole is arranged on the portion, located above the split rings, of the inner wall of the arrangement cavity. Due to the adoption of the technical scheme, when the valve rod is axially stressed, force is transmitted to the check ring for hole by the split rings to complete rigid limitation, and the valve rod is effectively prevented from falling out; the accuracy of fit between the valve rod and the valve body is improved, machining and assembly difficulty is reduced, and working hours are reduced; an upper end spigot can be formed through casting, only a check ring groove needs machining, the weight of the valve body is reduced, and cost is reduced.