A PLANT DISEASE CONTROL COMPOSITION COMPRISING A CARBOXAMIDE COMPOUND REPRESENTED BY FOLLOWING 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 FLUDIOXONIL IS PROVIDED BY THIS INVENTION, AND THIS COMPOSITION HAS AN EXCELLENT EFFECT FOR CONTROLLING PLANT DISEASE.