The aim of this study was to test hypothesis that genotype TT in Czech Pied bulls, associated with higher leptinemia, will have significant effect on energy metabolism parameters in blood serum. The experiment was performed on the Czech Pied bulls in average age of 253 ± 13 days. The animals were sorted out into three groups according to the leptin genotype. The genotype TT was represented 20 animals, CT was represented 143 animals and CC was represented 127 animals. In the blood serum β-hydroxybutyrate (BHB) and non-esterified fatty acid (NEFA) were analyzed. One-way ANOVA revealed significant relation between serum concentration of NEFA and SNP genotype in leptin gene of Czech Pied bulls, but we failed to verify the hypothesis that genotype TT could affect some of monitored parameters.