Anti-tyrosinase assay guided isolation of marine-derived fungus Botrytis sp.led to separation of three ?-pyrone compounds.The structures of these compounds were elucidated by various physicochemical analytical methods.The bioactivities of these ?-pyrone derivatives were evaluated in terms of anti-tyrosinase activity.By correlating the bioactivities of these compounds with their structures,it concluded that the ?-pyrone with pentyl group gives highest anti-tyrosinase activity.