Iron nanoparticles exist naturally in the environment, it has distinct properties like reactivity, mobility and toxicity which can have potential harm to the nature when it accumulates in large amounts in the soil. Previous studies used varied levels and materials of iron nanoparticles to evaluate its effect on plants, our study aimed to evaluate the potential effect of Iron Nanoparticles (Fe2O3 NPs) seed priming on some Iraqi barley cultivars at the germination level. The Fe2O3 NPs successfully synthesized using Turmeric extract and examined using Ultraviolet-Visible (UV-vis), Fourier Transform Infrared spectrum (FTIR), Atomic Force Microscope (AFM), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX). In the experiment, the seed was primed with concentrations of NPs (0,3,6,9 mM) with varied priming periods (6,12, and 24 h) and evaluated the seed germination rate (%) and seed germination speed (h). The experimental data showed statistically insignificant suppression of the seed germination rate compared with control treatment for all cultivars which had 100% germination rate except 9 mM, which was marked significant compared with control treatment, while germination speed delayed and significantly affected by the increase in priming period at the concentrations (6 and 9 mM). The study concluded that Fe2O3 NPs barley seed priming can inhibit the germination and delay germination speed at high concentrations which may pose phytotoxic effect at high levels and long term exposure.