We examined the microo rganisms in reservoir water and obtained some corrupted the steel in reservoir, with multi-tube fermentation method.Incubating these microbes in different media in which there are different germicides with different concentrations, we screened more effective germicides to produce antiseptic paints.Discs made of the antiseptic paints were used to do bacteriostatic experiments.Long-time experiments were also done.The result showed that the No.22 germicide and its antiseptic paint are more effective materials, which can prevent the steel in reservoir from being corrupted.