A total of 256 fifty-six-day-old Noi broilers were allotted to 16 experimental units with 16 chickens for each in a completely randomized design to evaluate the effects of dietary lysine supplement on apparent nutrient digestibility, carcass characteristics and small intestine villi of Noi chickens. The experimental diets consisted of the control (0.8% lysine) and the other three treatments differed by adding 0.1, 0.2, and 0.3% more lysine for each treatment. The dietary crude protein and ME was 15% and 2,900 kcal/kg of feed, respectively. The digestibility of crude protein and overall mean of amino acids were gradually improved as the level of lysine increased. Dressing percent, breast/carcass ratio and length of intestinal villi were increased with extra lysine supplementation.