The present invention relates to a method for isolating cochlioquinone from a rice plant inoculated with a planthopper. When using the method for isolating cochlioquinone from a rice plant inoculated with a planthopper according to the present invention, not only it is possible to rapidly produce cochlioquinone but also large quantities of the substance can be produced with high efficiency and costs can be reduced, and thus can be used to advantage in the production of cochlioquinone and in various fields in which the substance is used.