The invention discloses a linkage mechanism for a vacuum oven and belongs to the field of vacuum ovens. The linkage mechanism for the vacuum oven comprises an eccentric wheel, a linkage rod and a jacking pressing piece and is characterized in that the eccentric wheel is covered with two layers of sliding plates, the upper-layer sliding plate is provided with an arch-shaped rail for controlling movement of an eccentric wheel shaft, the lower-layer sliding plate is provided with a notch, through which the eccentric wheel passes, one side of the linkage rod is connected with the side surface of the eccentric wheel, the other side of the linkage rod is connected with the jacking pressing piece, and the jacking pressing piece is in contact with a deflation valve. By adopting the linkage mechanism provided by the invention, a temperature and air pressure of a tank body in the vacuum oven can be more accurately controlled, opening and closing of an oven door are controlled through the linkagemechanism, and the linkage mechanism has the advantages of simple structure, reasonability in design, easiness in manufacturing and convenience in use.