The acaricidal activity of Fewry-med (10% zeta-zipermethrin) against Ixodes persulcatus was studied in laboratory and field conditions. The drug's doses of 0.01-0.005 g/m2 (as calculated for active ingredient) provided 100% death of ticks when forest areas (Tyumen' Province) were treated. The efficiency of treatment preserved within 31 days (the follow-up period). When Fewry-med was used in a dose of 0.005 and 0.01 g/m2, the soil levels of zeta-zipermethrin was lower than the maximum allowable concentration at days 7 and 14 after treatment. In the treated areas, the size of crawling representatives of the entomofauna restored at day 25. The drug may be recommended for industrial trials.