The objective of this study was to estimate the effect of a single-nucleotide polymorphism (SNP11646) in the FGF2 (Fibroblast Growth Factor 2) gene on the deregressed proof of breeding values (DRP) of Holstein sires (n = 149) for milk traits (milk yield, fat yield and percentage, and protein yield and percentage) and fertility (relative breeding value for own fertility – conception rate of heifers, cows, all females inseminated by the sperm of the sire, relative breeding value for conception rate of daughters – heifers, cows, all females). The differences between genotypes for milk performance were not significant. The lowest DRP for milk performance were found for AA sires. For fertility, sires with this genotype had the best values both for the maternal genetic effect (conception rate of the daughters) and for the direct genetic effect (fertility of the sire). For conception rate of the daughters, in some cases, the differences reached the threshold of significance. Thus, the results indicate coincidently with other studies the potential opposing effects on milk performance and fertility. FGF2 SNP11646 is still of interest for future cattle breeding studies.