Abstract: "FENG LE No 1" is a new fumigant miticide which is highly effective and very safe to honey bees, Its active ingredient is bromopropylate, The results of experiments carried out both in and out of the laboratory showed that the LC₅₀ and LC₉₅ of bromopropylate active ingredient in"FENG LE No 1”against Tlarroa j acobsorci were 0,268/m³ and 2,92g/m“respectively，while 71.45g/m³ and 21g,7g/m³ against bees, The latter were 274.8 and 74.9 times higher,"FENG LE No 1" is effective against both Tlarroa jacobsoni and Tropilaelaps clareae, For one hive，the control effect of a dosage of 0,44-0,458 of active ingredient against }arroas exceeded g3}o,The hive was treated once every 5 days, and after 3 applications the bees remained normal, The residual amounts of bromopropylate in the honey samples taken on day 2,6,15 after 3 applications were measured and averaged at 0.0296，0.0208 and 0.0120 mg/kg respe-ctively，much lower than the FAP/WHO standards for fruits and vegetables,"FENG LE No 1”is feasible to apply oui;side the hive，and in Ghina,its effectiveness in the outside application is 15 times higher than the current inside application.Therefore，it can be used in many more cases.

Key words: Tlarroa jacobsona, Fumigant miticide, FENG LE No 1