The present study was undertaken in order to investigate the effect of CuO nanoparticle which was prepared by green method. Also, evaluate the median concentration on total Protein and Carbohydrate content of treated larvae with Achilea fragrantissima extract and CuO nanoparticle comparing with control. The effects of tested materials were examined on the activities of acetylcholinesterase (AChE) and glutathione S-transferase (GST). The results revealed inhibition of all biochemical activities except in GST activity was increased in treatment by Achilea fragrantissima extract.