The field work was carried out at the Experimental Farm of the DesertResearchCenter, Balosa region, North Sinai Governorate, during winter season of 2014/2015. The experiment was conducted to investigate the effect of nano-TiO₂ at the rate of 1, 2 and 3 gm /L on growth, yield and chemical composition of onion variety Giza Red grown in sandy soil. Result revealed that growth parameters, chlorophyll contents, chemical contents, yield and its components increased with increasing nano-TiO₂rate. No significant differences between nano-TiO₂ at the rates of 2 and 3 gm/L on bulb dry matter (%), total yield and nitrogen content.