A plant disease controlling composition, containing a carboxamide compound represented by formula (I):wherein R1 represents a hydrogen atom or a methyl group andR2 represents a methyl group, a difluoromethyl group or a trifluoromethyl group, anda pyridazine compound represented by formula (II)whereinA1 represents a chlorine atom, a bromine atom, a cyano group or a methyl group, andA2 represents a hydrogen atom or a fluorine atom.
