PURPOSE: To provide a new aziridine compound having trifluoromethyl group and useful as a raw material for physiologically active substances such as pharmaceuticals and agrochemicals and functional organic compounds such as liquid crystals, surfactants, dyes and optical resolution agents.

CONSTITUTION: This aziridine compound having trifluoromethyl group is expressed by formula I (R1 is H, an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group or a group produced by substituting one or more carbon atoms of the above hydrocarbon groups with hetero atoms selected from among O, S and N), especially an optically active compound of formula II (C labeled with * is an asymmetric center carbon atom), e.g. N-benzyl-2-trifluoromethylaziridine. The compound of formula I can be produced by the cyclization reaction of a compound of formula III with a compound of formula IV (R2 is an alkyl, an aryl or an aralkyl; X is a halogen) in the presence of a base. The compound of formula II is produced by the cyclization reaction of a compound of formula V with the compound of formula IV.