This study aimed to assess the effect of titanium dioxide (TiO2), Thyme essential oil and a mixture of both on the quality of chicken fillets .Fresh chicken breast fillets samples were treated with TiO2 nanoparticles as a trial (Ⅰ ) , Thyme oil (2%) as a trial (Ⅱ ) individually and in mix of both( trial Ⅲ). All samples were examined during cold storage (4±10 c) at zero, 2, 4, 6, 8 , 10 , 12 and 14 days from examined sensory, bacteriologically and chemical point of view. The results indicated a positive effect on the shelf life of treated samples as compared to untreated ones especially in trial (Ⅱ). On the other hand, there was a good antibacterial activity of such treatment on APC, Psychrotrophic and coliform counts. Also , the results showed that pH, TBA and TVN values were increased but not reached to spoilage(6.4) in all treated samples which treated with Thyme oil 2% give the best effectiveness followed by TiO2 and combination of both.