The research aimed at evaluating the slaughter value and meat quality of 32 fatteners fed diets supplemented with an antibiotic growth promoter (control group (C) – 16 animals) or with zinc oxide (experimental group (E) – 16 animals). In a two-stage fattening process, the control fatteners were given an isoenergetic mixture with a 5% addition of a premix containing flavomycin (100 mg/kg pmx), whereas the experimental animals received the antibiotic-free premix. In the I stage of fattening (up to 50 kg of body weight), the diets of the experimental fatteners was supplemented with 0.05% ZnO. The growth rate and feed utilization in groups C and E were comparable. No statistically significant differences were found in the slaughter traits of the groups examined. The chemical composition of the longest dorsal muscles and the percentage of the lipid fraction of musculus longissimus SFA, PUFA and MUFA, were also alike. Compared to the control group, the per cent of SFA was observed to decrease and those of MUFA and PUFA to increase, which was found beneficial. Zinc concentration in meat was within the recommended norms. The results obtained indicate the possibility of producing good-quality carcass and pork without the addition of an antibiotic growth promoter. No significant differences were obtained between fatteners fed diets supplemented with an antibiotic or zinc oxide as regards fattening results, slaughter value and meat quality.