The invention discloses a transition device of a hydraulic valve stand. The transition device comprises a parent plate mounted on the hydraulic valve stand and a cover plate, the parent plate is provided with a first through hole communicated with an oil hole in the hydraulic valve stand, the cover plate detachably connected with the parent plate in an attached manner is provided with a second through hole capable of being communicated with an oil hole of a hydraulic valve, the surface, attached to the cover plate, of the parent plate is provided with an upper groove communicated with the first through hole, and the second through hole is communicated with the upper groove. The parent plate is mounted on the hydraulic valve stand, the first through hole of the parent plate is enabled to be communicated with the oil hole in the hydraulic valve stand, the cover plate is mounted on the parent plate, and the first through hole is communicated with the second through hole which is communicated with the oil hole of the hydraulic valve. The upper groove is formed in one end of the first through hole, so that relative range of the first through hole and the second through hole can be increased, the parent plate can fit the cover plate provided with the second through hole at different positions, and types of the hydraulic valves that the parent plate can adapt to are expanded. During use, only the cover plate rather than the parent plate needs to be replaced, and accordingly cost of the transition device is reduced.