Laboratory experiments were carried out during the period from July 2009 to May 2010, to study the efficicency of three concentrations (2.816, 1.77 and 0.79 ppm) of Radiant compound 12% against adult stages of the predatory mite Cunaxa setirastirs (Hermann)  and the sequence effect of the three concentrations against the eggs resulted from treated females by LC₅₀ under laboratory conditions 25±1°C and 75±5%R H. Results indicated that  the three concentrations caused high effect on duration of preoviposition, oviposition and postoviposition, where by lasted 7.2, 21.7 & 2.9 days, 5.3, 26.5 &4.6 days and 4.3, 29.0 & 5.5 days at 2.816, 1.77 and 0.79 ppm, respectively, at 2.816 , 1.77 and 0.79 ppm and 4.3, 29.0 & 5.5 days at 0.79 ppm, respectively,compared with 3.4, 40.0 and 3.9 days in control. Also, the female and male longevity were high affected by the three concentrations. The high decreased in longevity period occurred at 2.816 ppm which was estimated by 32.7days for female and 19.3 days for male compared with 45.7 and 34.46 days for female and male, respectively, in control. On the other hand, the three concentrations caused high reduction in the average number of deposited eggs per female, it was 54.6, 73.3 and 84.3 eggs/female treated by 2.816, 1.77 & 0.79ppm, respectively, compared with 124 eggs in control. When eggs treated with Radiant,  the LC₅₀ , LC₂₅ and LC₁₀  were 1.6,0.618 and 0.43 ppm, respectively and prolonged the duration larvae, protonymph, dutonymph and tritonymph stages in both female and male.