To prevent an organic material from being damaged by a plasma at low temperatures below 80°C and to prevent intrusion of moisture and oxygen from the outside by forming films of a macromolecular polymer, silicon oxynitride and silicon nitride as an organic EL protective layer.

In this manufacturing method for an organic electroluminescent element, firstly a film of the macromolecular polymer is formed on the upper surface of a negative electrode 9 of an organic EL substrate in a decompressed vacuum vessel by plasma CVD by using an induction coupled plasma source as a plasma generator, and thereafter, the films of silicon oxynitride and silicon nitride 11 are formed on top of that. Antioxidant protective films 10 and 11 are formed on the upper surface of the organic EL element 9 by an ICP-CVD method.