Abstract. Linear type evaluations of 214 horses of the Old Kladrub breed for 32 traits were used to analyse the effect of variety (gray and black), sex (stallions and mares) and age. The linear model included the fixed effects of variety, sex and age and interactions variety x sex, variety x age and sex x age. Significant differences were found between the varieties in almost two thirds of the traits. The topline was longer and weaker in the black variety than in the gray one. The Shoulder of the gray horses was longer and more sloped than of the black one. The animals of the gray variety had a wider and deeper ehest. The stance of forelimbs and hind limbs was more correct in the gray variety than in the black one. Significant differences between sexes were observed in a few traits. Only 12 of 32 traits showed significant changes with age. In 10 of 32 traits, at least one of the interactions was significant. The estimates of this study characterise the Old Kladrub breed and its varieties in its current state and allow for more accurate evaluation of the horses.