This study investigated the effect of supplementation with chicken extract on plasma and colostrum protein compositions in lactating women. Thirty healthy pregnant women were evenly divided into the control (n = 15) or chicken extract (CE) group (n = 15). The CE group was given one bottle (70 mL/bottle) of chicken extract three times a day to provide 18 g protein from the 37th week pregnancy to 3 days postpartum. All women in the CE group consumed chicken extract at least for 2 weeks (18 +/- 5 days). High protein supplement was restricted in the control group. Blood samples were collected during the 37th week pregnancy and 3-day postpartum, and milk was collected during 3-day postpartum. The results showed that plasma total protein was significantly lower by 14% in the CE group compared with that in the control group during 3-day postpartum. Plasma epidermal growth factor (EGF) significantly elevated by 236% during 3-day postpartum compared with those during the 37th week pregnancy in the CE group. The levels of lactoferrin, EGF, and transforming growth factor-beta2 (TGF-beta2) in colostrum significantly increased by 34%, 62%, and 196%, respectively, in the CE group compared with those in the control group. However, the levels of total protein, casein, lactalbumin, and secretory immunoglobulin A in colostrum did not significantly differ between two groups. Therefore, supplementation with chicken extract increased colostrum levels of lactoferrin, EGF, and TGF-beta2, which are important for the growth and immune functions of the infants, in lactating women.