This study was carried out to investigate the impact of Fe2O3 NPs synthesized from mentha, onion and moringa plant extract at the concentrations of 20,40 and 60 and 80 ppm on wheat plant as fertilizer. Plant pigments chlorophyll a, b carotenoids as well as total pigments contents were investigated. Also, total phenolic components contents in wheat shoots were determined. The results showed that the foliar application of iron oxide nanoparticles at low concentrations (20,40 and 60 ppm) induced an increment in photosynthetic pigments and total phenolic compounds contents. beyond these concentrations an inhibitory effect was shown at 80 ppm concentration. Different sizes of nanoparticles showed different impacts on the studied criteria, small particle size induced more enhancement in plant pigments and phenols contents while larger sizes showed less impact.