To assess the effect of supplying garlic powder (GAR) in the diet on blood serum and egg yolk cholesterol, maize-soybean diets supplemented with 0 (NC), 0.5 (GAR_0.5), 1 (GAR₁),1.5% (GAR_1.5) as well as Tylosin (PC), were given to 200 hens as a completely randomized experiment throughout a 10 weeks production period. Blood samples for serum cholesterol determination were collected from wing vein of individual hen with two weeks intervals, and egg were collected once a week and subjected to cholesterol assay. Supplementation of diets with garlic powder and Tylosin had significant (p<0.01) effects both on serum and egg yolk cholesterol. The lowest serum cholesterl was obtained with GAR₁, while the NC gave the highest level of cholesterol. A similar trend was observed with yolk cholesterol, in which GAR₁ and NC were the treatments with the lowest and highest cholesterol. The results showed that inclusion of garlic powder significantly (p<0.01) decreased yolk weight, though there were no differences between the different level of the garlic powder. The correlation between yolk and serum cholesterol was negative and low (r=-0.09, p<0.05). In conclusion the results of this study clearly demonstrated that, there is, considerable advantages in using garlic powder rather than chemical reagents in hen rations and there would be even greater advantage both in results and in cost for either poultry industry and consumers, if garlic powder fed to the hens.