The present invention includes wickerol and a method for producing the wickerol. In the method for producing the wickerol, Trichoderma atroviride strain FKI-3737 (FERM ABP-11099 corresponding to FERM BP-11099) belonging to filamentous fungi is cultured in a medium, and the wickerol is accumulated in a culture, and then the produced wickerol is isolated and purified from the culture. A substance having inhibitory activity against influenza virus replication and containing the wickerol as an active ingredient, and an anti-influenza drug containing the wickerol as an active ingredient are obtained.
