A plant disease control composition comprising a carboxamide compound represented by following formula (I), wherein R represents a hydrogen atom or a methyl group, and Rrepresents a methyl group, a difluoromethyl group or a trifluoromethyl group, and one or more dithiocarbamate compounds selected from group (A) consisting of mancozeb, maneb, thiram and zineb is provided by the present invention, and this composition has an excellent effect for controlling a plan disease.