PROBLEM TO BE SOLVED: To provide an improved optical oxygen oxidation method for an organic compound in which reaction can be progressed by high speed and efficiency, and also, the use of a photosensitizer can be reduced or made needless.SOLUTION: Provided is an improved production method in the production of a product by the optical oxygen oxidation of a raw material organic compound, characterized in that a solution containing the raw material organic compound placed under light irradiation is injected with an oxygen-containing gas in the form of nanobubbles, and the state where the nanobubbles of the oxygen-containing gas are dispersed into the solution is retained, thus the optical oxygen oxidation reaction of the raw material organic compound is progressed to obtain the product.
