The invention discloses a novel switch cabinet valve mechanism. A large connecting rod I and a large connecting rod II can respectively rotate around a fixed pin I and a fixed pin II; a valve plate I and a valve plate II are hinged with each other through a cross rod I; a valve plate III and a valve plate IV are hinged with each other through a cross rod II; the valve plate I can rotate around a lower valve shaft; the valve plate IV can rotate around an upper valve shaft; the valve plate II is clamped in a lower valve chute through a screw stem I; the valve plate III is clamped in an upper valve chute through a screw stem II; the large connecting rod I and the large connecting rod II are respectively hinged with a small connecting rod I and a small connecting rod II; the top ends of the small connecting rod I and the small connecting rod II are respectively connected with the screw stem I; and the screw stem I is connected with the screw stem II through a wire rope. The mechanism can realize automatic opening or closing of the valve, and is characterized by strong integration performance, convenient installation, high structural strength, strong adaptability and the like.