The invention belongs to the technical field of valve devices and particularly relates to a semi-submersible type waterproof breather valve which comprises a valve bonnet and a valve body mechanism, wherein the valve body mechanism comprises an assembling column body and a connecting column body; the spiral cover of the valve bonnet covers the assembling column body; the first end of the assembling column body is fixedly mounted on the connecting column body; the connecting part of the assembling column body and the connecting column body extends towards a circumferential boss to form a flangering; an oblique cutting plane is formed at the second end of the assembling column; a countersunk head vent hole penetrating through the assembling column body and the connecting column body is formed in the oblique cutting plane; and the oblique cutting plane is covered with a platy waterproof gas-permeable membrane. Water drops on the gas-permeable membrane covering the oblique cutting plane can fall off the gas-permeable membrane at any time without being accumulated on the waterproof gas-permeable membrane; and the waterproof gas-permeable membrane can be manufactured into simple platy instead of a middle bulged shape through hot press molding, so that the manufacturing technology is remarkably simplified and the manufacturing difficulty and cost are reduced.