The aim of the present study was analysed and evaluated chemical parameters of chicken breast and thigh muscles after addition of humic acids and probiotic into diet for broiler chicken. A total of 200 pcs Ross 308 broiler chickens were divided into 4 groups (n=50). The control group of chickens was fed with complete feed mixtures without any additives. Chickens in experiment groups were fed a diet containing: P1 (1% of humic acid), P2 (1% of humic acid and probiotic supplement Lactobacillus fermentum) and P3 were fed with complete feed mixture containing combination of starter feed mixture (1. - 21. day) with coccidiostaticum Diclazuril and growth feed mixture (21. - 35. day) containing Salinomycinum sodium. Besides, the groups were kept under the same conditions. Fattening period lasted for 42 days. Chicken meat was analyzed for content of water, crude protein, fat and cholesterol. Based on the results, we can state that the application of humic acids or the combination of Humac Natur with probiotic did not affect the chemical composition of the breast muscle. In the breast muscle, the protein content in the experimental group P3 with the coccidiostat (22.98 g.100 g-1) was reduced (p ≤0.05) compared to control group (23.42 g.100 g-1). In the case of thigh muscle was significantly higher content of fat and cholesterol (p ≤0.05) in chickens feeding with addition of Humac Natur (fat - 9.08 g.100g-1; cholesterol - 0.86 mg.100g-1) and similar results were recorded in experimental group with combination of Humac Natur and probiotic (fat - 9.15 g.100g-1; cholesterol - 0.86 mg.100g-1) compared to control group (fat - 7.15 g.100g-1; cholesterol - 0.70 mg.100g-1). From a general point of view, we can recommend the application of Humac Natur, respectively combination Humac Natur with probiotics in feeding of broiler chickens Ross 308.