Abstract. Conformation traits of 284 Polish konik mares used in breeding until 2005 were analyzed including pedigree information on 477 individuals. Average inbreeding coefficient was in SK Dobrzyniewo 5.9 %, in SK Kobylniki 5.1 %, and 5.6 % in SO Sieraków. No significant effect of inbreeding on conformation traits was observed. Heritability was estimated as: 0.65 (±0.13) for height at whither, 0.22 (±0.14) for circuit of chest and 0.65 (±0.13) for circuit of cannon. Negative phenotypic trend was observed for girth circumference and positive for circuit of cannon. No significant genetic trends were observed for the analyzed traits, which agrees with the assumption of breeding program in genetic reserve flocks.