A method for producing a rubber diaphragm, comprising: (a) preparing materials; (b) primary forming: putting a first rubber film into a lower mold cavity of a diaphragm mold, covering the film with a canvas, positioning the canvas via a mold ring, switching on a primary upper mold on a vulcanizer, pushing the mold into a center of a hot plate of the vulcanizer, and performing primary forming for 30-40 seconds under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa; and (c) secondary forming and curing: taking the mold out, removing the upper mold, putting the second rubber film into a mold cavity and switching on a secondary upper mold, pushing the mold into a center of the hot plate, and performing secondary forming and curing for 5-5.5 minutes under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa. A rubber diaphragm produced by this method.