This investigation was designed to determine the effect of garlic juice on some kidney function parameters in layer chicken. Blood samples were collected via jugular vein from 20 animals before treatment with garlic juice for check urea, creatinine, uric acid, calcium ion, albumin and amylase in serum. The animals received garlic juice orally in dose (0.02ml/day) for 15 day and blood samples were collected for check the kidney function parameters which mentioned above. The result of this study revealed a significant decrease in all parameters which mentioned above with un significant decrease in serum urea concentration. These results may interpreted that garlic juice may increase glomeruler filtration rate GFR of nephrone and tubular secretion. The conclusion from this study that garlic juice increase kidney performance from the decrease in serum concentration of kidney function parameters.