In order to investigate the effect of two different feed additives, including an a prebiotic (Fructomix) and Peppermint essential oil on growth performance, digestibility, blood parameters, carcass characteristics, gut morphology and immune response of broilers and also to compare them with an antibiotic growth promoter (Virginiamycin), a 6 week experiment was designed and conducted. In this experiment, 336 Ross 308 male broilers were used in a completely randomized design with 7 treatments, four replicate pens per treatment and 12 chicks per pen. Chicks were fed either a Corn-Soybean meal basal diet (control group or treat 1) or the basal diet supplemented with 200g/ton Virginiamycin (treat 2), 200 mg/kg Peppermint oil (treat 3), 400 mg/kg Peppermint oil (treat 4), 0.5 kg/ton Fructomix (treat 5), 0.5 kg/ton Fructomix plus 200 mg/kg Peppermint oil (treat 6) or 0.5 kg/ton Fructomix plus 400 mg/kg Peppermint oil (treat 7). Performance traits, including weight gain and feed intake, were measured weekly. In the entire experimental period, treatment 2 had highest average daily gain (50.63) and feed intake (87.49) that were significantly different with all other treatments. Also treatment 2 had the best feed conversion ratio (1.72) that was significantly different with other treatments except treatment 3. In day 21 of rearing period, in order to measure crude protein (CP) and fat digestibility, fecal samples were collected. Two days before the collection of feces (day 19), 0.5 kg/ton Celite (as an acid insoluble ash source) was added to the diet. Highest CP digestibility was observed in treatments 3 (86.45) and 2 (85.05) respectively, which were significantly different with other treatments except treatment 4. Lowest fat digestibility was related to treatments 7 (73.75) and 5 (75.61) that were different (p= 0. with treatments 1, 2 and 3. At the end of the experiment (day 42), two birds per replicate (8 birds per treatment) were selected, according to mean weight of each replicate, and slaughtered for measuring gut weight (GW), ready to cook carcass weight (RC-CW), abdominal fat (AF) and also investigating morphology of the gut. Before slaughter, for measuring concentration of serum lipids and proteins, blood was collected from wing vein. RC-CW was similar in all treatments. The lowest relative gut weight (according to body weight), belonged to treat 2 (4.9 percent) but it was not different from other treatments. AF was lowest in treatments 5 (1.96 percent) and 7 (2.05) that had significant difference with treatments 1 and 2. In duodenum, highest villus height (1489) and lowest crypt depth (205) were related to treatment 2. Lowest villus height: crypt depth Key words: Broilers, prebiotic, Peppermint oil, Virginiamycin, performance, digestibility, immune response