Keywords: B.alexandrina Anagalis arvensisCopper oxide Molluscicide Nanoparticles Histopathology Nanotechnology has received more attention in the field of control of intermediate hosts. In the present study, copper nanoparticles were fabricated and characterized using scanning electron microscopy (SEM), transmission electron microscope (TEM), x-ray fluorescence (XRF) and fourier transform infrared (FTIR). Improvement of the molluscicidal activity of Anagalis arvensis ethanolic extract was made using CuO NPs by forming plant nanocomposite (ACuO NC). The results showed that ACuO NC has high molluscicidal activity against B. alexandrina snails; recording LC 50 and LC 90 were 1.76 and 3.16 ppm, respectively. Also, biochemical parameters (Total protein, ALT, AST and ALP) revealed highly significant changes in treated snails with sublethal concentrations (LC 10 and LC 25 ) of ACuO NC. However, histopathological changes occurred in the hermaphrodite glands of snails exposed to these concentrations of nanocomposite were detected, where, the ova and sperms degenerated and there were losses of connective tissues between acini. ACuO NC was more safety when tested against the biological indicator Daphnia magna. These observations prove that ACuO NC has potent molluscicidal activity against the intermediate hosts of Schistosoma mansoni with more safety for aquatic environment.