Pitamin is a component of pine bark extract that exhibits antimicrobial activity and a variety of physiological effects. This study was carried out to investigate the effects of dietary pitamin as an organic livestock feed additive in broiler chickens. A 35 day trial was conducted to determine the influence of dietary premix containing 5% pitamin; investigated parameters included blood lipids, growth performance, quality characteristics of carcasses, and changes of caecal microbials in broiler chickens. Chickens were randomly divided into groups that were untreated (control), treated conventionally with antibiotics in the absence of premix, received 0.1% or 0.2% premix containing 5% pitamin. Plasma lipids were lower in groups fed diets with pitamin premix (p＜0.05). The body weight gain from broiler chickens fed with the diet containing 0.1% pitamin premix and antibiotics was similar, and was significantly higher than that of the other groups (p＜0.05). The weight of breast muscle and thigh meat of carcasses was similar, and was higher than that of the control group (p＜0.05). Abdominal fat and thymus index from chickens receiving either pitamin-supplemented premix was significantly lower and increased, respectively, that of the antibiotic and control groups (both p＜0.05). The chickens on the pitamin premix-supplemented diets evidenced significantly higher caecal levels of Bifidobacterium species as compared with the chickens on the control diet (p＜0.05). These results suggest that feeding a diet supplemented with a 0.1% premix containing 5.0% pitamin for 35 days maintains the production of broiler chickens at a level comparable to that obtained from the use of antibiotics.