The severity of rice stem rot caused by Helminthosporium sigmoideum when the plants were treated with both, excision and with varied inoculum quantities of sclerotia was studied. Severity of rice stem rot increased by leaf cutting-off and paralleled with the quantity of the sclerotial inoculum, but the former treatment was more effective than the latter. Interaction between the leaf-cutting and the quantity of sclerotial inoculum was not recognized.