A mold for forming a gum cover for isostatic cool pressing is characterized in that a mold seat, an inner mold, an outer mold and an exhaust pipe are included; the inner mold is arranged on the upper end face of the mold seat; the outer mold is arranged on the upper end face of the mold seat and arranged on the periphery of the inner mold in a sleeving manner, and a cavity matched with the gum cover is formed between the inner side wall of the outer mold and the outer side wall of the inner mold; and the exhaust pipe is arranged on the outer mold in a penetrating manner, the inner end of the exhaust pipe communicates with the cavity, the outer end of the exhaust pipe can be connected with an exhaust device, and the inner end of the exhaust pipe is arranged in the manner of being close to the top face of the cavity. The invention further discloses a method for forming the gum cover through the mold. Compared with the prior art, the mold has the beneficial effects that processing and manufacturing are easy, manufacturing is fast, and cost is low.