Efficacy of three acaricides (Ortus 5% EC, Milbeknock 1% EC and Cascade 10% DC) and predatory insect; Chrysoperla carnea Stephens was evaluated on the European red mite Panonychus ulmi Koch (Acari: Tetranychidae) movable stages infested apple orchards during the two successive seasons; 2012 and 2013 at Darawa village, Ashmon, Menoufia governorate, as well as determining the biochemical changes in the treated insects. The results show that, The highest reduction percentages of P. ulmi movable stages during 2012 and 2013 seasons were recorded with Ortus followed by Milbecknok then the predatory insect; C. carnea, while the lowest reduction percentages were recorded with Cascade. The effect of the two acaricides Ortus and Milbecknok (the highest toxic acaricides) on the major biochemical components of P. ulmi adult females showed that, the acaricide Ortus achieved high effects on the total lipids content and the two enzymes Acetylcholinesterase (AchE) and Glutathione-S-transferase (GST). The acaricide Milbecknok recorded high effects on the total lipids and carbohydrates contents and lipase, trehalase, amylase, AchE and GST enzymes. The two acaricides Ortus and Milbecknok are effective in controlling European red mite on apple trees and this can be attributed to abnormal changes of the major biochemical components in the treated mites. The predatory insect; C. carnea has efficient predation against P. ulmi and resulting increasing in the reduction of mite populations.