Provided is an azole derivative superior in disease-controlling activity contained as an active ingredient in agricultural or horticultural chemical agents. The azole derivative according to the present invention is represented by the following General Formula (I): (in Formula (I), R 1 represents an unsubstituted or substituted C 1 -C 6 -alkyl group； R 2 represents a carbonyl group-containing functional group, wherein the carbon atom in the carbonyl group is bound to the carbon atom in the cyclopentane ring substituted with R 1 and to a hydrogen atom, a hydroxyl group, R 3 , OR 3 , or NR 3 R 4 ； R 3 and R 4 each represent a C 1 -C 6 -alkyl group, a C 2 -C 6 -alkenyl group, or a C 2 -C 6 -alkynyl group； Y represents a halogen atom, a C 1 -C 4 -alkyl group, a C 1 -C 4 -haloalkyl group, a C 1 -C 4 -alkoxy group, a C 1 -C 4 -haloalkoxy group, a phenyl group, a cyano group, or a nitro group； m is 0 to 5； and A represents a nitrogen atom or a methine group).
