The study evaluated the efficacy of ozone as a fumigant to kill Ligurian leafhopper (Eupteryx decemnotata) on rosemary growing under cover. Treatment of rosemary plants with 120 ppm ozone for 2 min resulted in 33.88-71.90% effectiveness of killing adult and larval leafhopper. Treatment of rosemary plants with 595 ppm ozone for 10 min resulted in 70.24-91.66% effectiveness of killing insects, however phytotoxixity ranged from 11.25% to 89.17%. These data demonstrate the potential usefulness of using ozone in managing rosemary plants and possibly other herbs.