To provide a highly reliable method for curing an ultraviolet rays-curable resin, a method for manufacturing a flat panel utilizing it, and an ultraviolet rays irradiating apparatus which is useful for practicing these methods, is inexpensive, exhibits low consumption of electric power, has a long lifetime and is miniaturized.

The method for curing holds oxygen concentration on the resin surface at 5 Vol.% or lower when the ultraviolet rays-curable resin is irradiated with ultraviolet rays from a light emitting diode. The apparatus is composed of a supporting tool for supporting a body to be processed, a means for irradiating with the ultraviolet rays from the light emitting diode, and a means capable of controlling the oxygen concentration on the surface of the body to be processed by feeding an inert gas around the body to be processed.