A fungicidal composition is provided. A fungicidal composition comprising synergistically effective amounts of (a) a carboxylic acid amide derivative of the formula (I) or its salt: wherein B is a heterocyclic group which may be substituted; each of R1 and R2 which are independent of each other, is alkyl; X is halogen, alkyl or alkoxy; and n is an integer of from 0 to 5, and (b) at least one fungicidal compound selected from the group consisting of an azole compound, an anilinopyrimidine compound, a triazolopyrimidine compound, a strobilurin compound, an N-halogenothioalkyl compound, a pyridinamine compound, a bicarbonate, an inorganic sulfur compound, a dithiocarbamate compound, an organic chlorine compound, a dicarboxyimide compound, an amine compound, a phenylpyrrole compound, a benzophenone compound, a dinitrobenzene compound, a piperidine compound, a morpholine compound, etc.
