The objective of this study was to evaluate an association between the polymorphism of the porcine pituitary-specific transcription factor gene (POU1F1, previously called PIT1) and carcass quality in F2 animals (grandparents: Zlotnicka Spotted boars and Polish Large White sows) being a part of experimental material prepared for a QTL mapping project. The analysis covered a total of 188 F2 offspring of 13 males and 67 females (F1 generation). The RsaI PCR/RFLP polymorphism of the POU1F1 gene was identified and the least squares method was used to evaluate the significance of its effect on the value of carcass quality traits. Three POU1F1/RsaI genotypes were identified in F2 porkers: EE (n=32), EF (n=68) and FF (n=88). Twenty-four carcass quality traits were measured after 24 h of cooling. The POU1F1/RsaI genotype proved to have a significant effect on the following traits: weight of ham bone and bacon including ribs, fat thickness at the lower back (point K3), over the loin, and average fat thickness (mean of five measurements). These results confirm that the POU1F1 gene may be linked to the gene/genes affecting fat deposition in the pig carcass. Moreover, pigs with the EE genotype had a greater loin eye area and showed a higher meat weight and content of carcass than animals of both EF and FF genotypes (unsignificant association), which suggests that a further study is necessary to confirm or exclude the effect of the POU1F1 gene on these traits.