Abstract: The present study was designed to determinate the effect of propolis as a feed additive on the serum bilirubin and albumin content of female and male chickens. Broiler chickens hybrid Hubbard JV (n=500) were divided into five groups in each gender (control – C and four experimental groups E1 – E4). Experimental chickens received a propolis extract in feed mixture in various doses (E1 – 150 mg/kg; E2 – 450 mg/kg; E3 – 600 mg/kg; E4 – 800 mg/kg). The group that received feed without propolis addition served as the control. Contents of albumin and bilirubin were determined with spectrophotometer. Supplementation of the diet with propolis in the dose of 600 mg/kg significantly (P<0.05) increased albumin content in male chickens. Propolis addition to diets may be a source for antioxidant capacity in human and animals.