Anti-theft device for oil extraction wellhead

The utility model discloses an oil extraction wellhead anti-theft device which comprises a fixing ring, a vertical pipe is fixedly installed on the upper surface of the fixing ring, a fixing ring is fixedly installed on the top of the vertical pipe, a cover plate is hinged to the upper surface of the fixing ring through a hinge, a box body is fixedly installed on the inner wall of the fixing ring, and an L-shaped rod is inserted into the top of the box body. The top of the L-shaped rod penetrates through the fixing ring and extends out of the fixing ring, a sliding plate is arranged in the box body, the L-shaped rod is fixedly connected with the sliding plate, a fixing plate is fixedly installed on the surface of the L-shaped rod, clamping rods are fixedly installed on the two sides of the lower surface of the fixing plate, and the bottoms of the clamping rods are connected with the upper surface of the sliding plate in a clamped mode. According to the anti-theft device for the oil extraction wellhead, the L-