In order to provide a highly reliable organic EL element, a first step in which a deposition material is heated and vaporized in a deposition chamber in which the pressure is reduced and a second step in which a layer included in an EL layer is deposited in the deposition chamber are performed while exhaustion is performed and the partial pressure of water in the deposition chamber is measured with a mass spectrometer. Alternatively, the deposition chamber in the deposition apparatus includes a deposition material chamber and is connected to an exhaust mechanism. The deposition material chamber is separated from the deposition chamber by a sluice valve, includes a deposition material holding portion including a heating mechanism, and is connected to a mass spectrometer and an exhaust mechanism.