The invention discloses an electromagnetic type separating valve which comprises a separating valve main body, wherein the separating valve main body is internally provided with an air inlet channel and a nitrogen discharge channel; one end of the nitrogen discharge channel is communicated with a molecular tower; the other end of the nitrogen discharge channel is communicated with a nitrogen discharge port in the separating valve main body; and a one-way valve only allowing materials to get out is arranged outside the nitrogen discharge port, and is movably connected with the separating valve main body. The invention discloses a method for increasing the life of an oxygen making machine. The electromagnetic type separating valve is mounted in the oxygen making machine. When the oxygen making machine does not works, the one-way valve exerts a sealing function, external greasy dirt and damp air can not enter a nitrogen storage cavity through the nitrogen discharge port and the molecular tower to be contacted with a molecular sieve, so that the service life of the molecular sieve is prolonged, then the life of the oxygen making machine is increased. When the oxygen making machine works, the one-way valve is opened, the nitrogen discharge function of the oxygen making machine is met, and both sealing and nitrogen discharge functions are exerted. The electromagnetic type separating valve and the method for increasing the life of the oxygen making machine have the advantages that the structure is simple, the concept is ingenious and the life of the oxygen making machine is increased effectively.