Provided is an antifungal composition containing a cyclic N-sulfonylamine compound, a cyclic N-sulfonylimine compound or a cyclic N-sulfonyloxaziridine compound, each having an antifungal activity, as an active ingredient. An antifungal composition containing a compound represented by the formula (1) :whereinring A is an optionally further substituted 5- to 7-membered heterocycle, and the 5- to 7-membered heterocycle is optionally condensed with 1 or 2 rings selected from an optionally substituted benzene ring and an optionally substituted 5- to 7-membered heterocycle,X is -N=, -NR2- or -O-;Y1 is a hydrogen atom, and Y2 is a hydroxy group or Y1 and Y2 may be joined to form a bond or -O-;R1 is a hydrogen atom, an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group; andR2 is a hydrogen atom or an optionally substituted hydrocarbon group,or a salt thereof as an active ingredient.