This paper aimed to through light on the importance of using biological agents as method for effective controlling the predatory mite was used in controlling phytophagous mites compare with Ortus 5% Sc pesticide that recommended representing incucumber yields in greenhouse. Increasing the time after releasing of Phytoseiulus persimilis, the reduction percentage of the pest increased gradually as the highest reductions (84.91%) recorded at 4th week while, using of chemical acaricide (Ortus 5% Sc) caused initial reduction reached 86.72% after 3 days of treatment. The difference in pest population for using each release and acaricide treatments appeared difference in pigments and leaves chemical contents. The obtained results showed significant differences in total yield of cucumber where, reachedmaximum 10.51 ton ⁄ feddanin case of using Ortus followed by 7.53 and 5.47 ton ⁄ feddan for using release of predatory mite, P.persimilis and control, respectively.