This study was conducted to evaluate the effect of phase-feeding on nitrogen excretion and carcass yield of Cobb500 broiler chickens by completely randomized design into 4 treatments: three different feeding phases 0-21, 22-35, 36-42 days was control treatment; treatment 1 was 0-21, 22-28, 29-42 days of feeding phases; treatment 2 with feeding phases 0-14, 15-35, 36-42 days and treatment 3 with feeding phases 0-14, 15-28, 29-42 days. Each treatment was replicated 4 times with 2 chicks at 1 day of age per replication. The diets contained 21.0, 19.5 and 18.0% crude protein (CP) which correlated to three different phases as starter, grower and finisher, respectively. The results showed that the different significance of nitrogen intake, nitrogen balance and nitrogen retention among treatments were found only at finisher period (P