The objective of the present study was to establish age relationships for hepatic and whole blood glutathione (GSH) in male broiler chickens, quail, and turkeys utilizing lines within each poultry species with different rates of growth. Liver and blood samples were obtained from three quail lines (light, medium, and heavy) at 3 and 6 wk of age, from two turkey lines (light and heavy) at 10 and 20 wk of age, and two broiler lines (medium and heavy) at 3, 5, and 7 wk of age. With the exception of the heavy turkey line, older birds generally exhibited higher hepatic GSH concentrations than younger birds. There was no apparent age-related difference in whole blood GSH, nor was whole blood GSH correlated with hepatic GSH in any poultry species.