The aim of the experiment was to determine the influence of probiotic preparation on productive parameters and carcass characteristics of broiler chickens. Totally 60 one-day-old chickens of Ross 308 were divided in two groups: control group (n=30) received drinking water without any additives and experimental group (n=30) received probiotic preparation in dose 2 ml per 1 l of drinking water from day 1 to day 42 of fattening. The probiotic preparation contained the strains of Lactobacillus casei CCM 3775 (3.86x106 CFU.g-1), Lactobacillus plantarum 24001 (3.86x106 CFU.g-1) and Saccharomycces cerevisiae MUCL 39885 (7.00x103 CFU.g-1). Broiler chickens were feeding ad libitum with commercial feed mixtures. Individual body weights of all birds, feed conversion ratio per group were determined in 21 and 42 day, total mortality rate we recorded in 42 day of fattening period. Carcass quality of broiler chickens was determined at the end of the experiment. The supplementation of probiotic affected positively body weight (p<0.05) in broiler chickens in 21 and 42 day of fattening. Feed conversion ratio in 21 and 42 day was similar in control and experimental groups. Total mortality in 42 day was positive affected (p<0.05) by supplementation of probiotic preparation in drinking water. The probiotic no significant (P˃0.05) affected percentage of breast and thighs from carcass body, weight of giblets and carcass yield. The addition of probiotic significantly (P<0.05) reduced the content of abdominal fat in carcass body.