Among the diseases occurring in cereals, leaf blight control agents are few in number and do not yet exhibit a sufficient effect. Therefore, in order to provide a novel leaf blight control means for the stable production of cereals and a method for said leaf blight control means, the present invention provides a method in which leaf blight that occurs in cereals is controlled by treating a cereal, the soil in which the cereal is cultivated, or the seeds of the cereal with an effective dose of fluoroimide.