Provided is a novel anti-HCV agent including as an active ingredient a peroxide derivative represented by the general formula (I). In the general formula (I), C represents an alicyclic hydrocarbon ring group which may be substituted, n represents an integer of from 1 to 6, and R represents a hydrogen atom or a hydroxyalkyl group. The peroxide derivative exhibits potent anti-HCV activity by remarkably suppressing HCV-RNA replication.