Abstract: A method for easily and stably producing a superoxide by selectively generating the superoxide or a radical containing the superoxide at a high purity; a method for easily evaluating the superoxide scavenging ability of a subject sample; a device for easily and stably producing a superoxide by selectively generating the superoxide or a radical containing the superoxide at a high purity; and a device for easily evaluating the superoxide scavenging ability of a subject sample are provided. The method for producing a superoxide includes: a step (a) for preparing a solution for determination; a step (b) for forming a spin adduct/radical for determination; a step (c) for acquiring a spectrum for determination; a step (d) for determining similarity; a step (e) for acquiring flavin concentration; a step (f) for preparing a starting material solution; and a step (g) for generation.