The utility model relates to a show dark rod -type valve of opening off state, the valve gap is fixed in the valve body top, the valve gap top be provided with with the coaxial cylindric opening of valve rod, opening top be fixed with with the fixed cover of cylindric of the coaxial setting of valve rod, the valve rod top is fixed with cylinder valve rod cover, it shows the cover to have cup jointed the shaft type between valve rod cover, the fixed cover, the interior circle that shows the cover with the lateral wall threaded connection of valve rod cover, its outer lane with fixed cover inner circle sliding connection, show the keyway that link up about vertical being provided with in cover outer lane, fixed cover inner circle with be provided with on the relative position of keyway vertical setting and with the key that the keyway matches each other. Through the design to the valve rod cover, make it form the linkage with showing the cover, in the rotary valve hand wheel, show that the cover can reciprocate to reach the mesh that shows gate valve standard -sized sheet position and complete shut -down bit position. The problem of unable demonstration valve open off state 's technique is solved.