A composition comprising a carboxamide compound represented by formula (I):wherein R1 represents a hydrogen atom or a methyl group, and R2 represents a methyl group, a difluoromethyl group or a trifluoromethyl group, and ethaboxam is provided by the present invention. This composition has excellent effect for controlling plant disease.本發明提供一種組成物,其包含以式(I)表示之甲醯胺化合物:其中R1表示氫原子或甲基,及R2表示甲基、二氟甲基或三氟甲基,及噻唑菌胺(ethaboxam)。此組成物具有極佳防制植物疾病之效果。