In this study, it was investigated the effect of clove oil supplementation at increasing levels into laying hens’ diets on performance, egg quality traits, some blood parameters and yolk TBARS (Thiobarbituric Acid Reagent) values. For this purpose 96 Lohman white laying hens, 28 weeks of age, were divided into four treatment groups. Control group was fed with basal diet (C) and treatment groups were fed with diets formed by addition of clove oil at 50 ppm (CO1), 100 ppm (CO2) and 150 ppm (CO3), respectively. During the trial, feed and water were given as ad-libitum, and poultry house was illuminated for 17 hours. Experiment lasted for 13 weeks. Addition clove oil at increasing rates into diet did not affect the live weight. The data analysed as polynomial showed that supplementation of clove oil into layer diet linearly improved feed conversion ratio and increased the egg production. But, daily feed consumption, egg weight, damaged egg ratio and egg quality parameters were not affected by treatments. Serum parameters such as triglyceride, glucose, aspartate aminotransferase, alanine aminotransferase and calcium were not affected by the clove oil supplementation. TBARS values in C, CO1, and CO2 were found higher than the CO3 group fed with diet including 150 ppm clove oil. In conclusion, clove oil at 150 ppm level in diets of laying hens could be used due to extend the egg shelf life and to decline serum cholesterol content.