The invention relates to a design method of a millimeter wave E-plane filter and in particular relates to a millimeter wave E-plane filter for supporting a vector machine to model for a diaphragm and a diaphragm modeling method. The millimeter wave E-plane filter for supporting the vector machine to model for the diaphragm is characterized by at least comprising a rectangular waveguide (1), two or more metal diaphragms (2) and an E-plane cavity in the right middle of the rectangular waveguide (1), wherein the E-plane cavity is parallel to a length direction of the rectangular waveguide and comprises the metal diaphragms (2); the metal diaphragms (2) are located in the center of a vertical rectangular waveguide E-plane and are parallel to the E-plane; adjacent metal diaphragms (2) are distributed at unequal intervals; the adjacent metal diaphragms are arranged along a straight line of the length direction of the rectangular waveguide; the surfaces of the diaphragms are vertical to the straight line of the length direction of the rectangular waveguide. Through the millimeter wave E-plane filter for supporting the vector machine for modeling the diaphragm, the design speed and precision of the filter are greatly improved, and a complex method for using electromagnetic calculation repeatedly is avoided.