The aim of this study was analyze of the efficiency of the natural ventilation in the horse stable and an indication of opportunities to improve its operation. The study was conducted in Glinik Zaborowski in the winter. The scope of the research included measurements of air velocity with opened and closed windows and gates. Based on the results of the measurements and observations, it was found that the efficiency of the ventilation was very low. Average values of the air flow ranged from 0.06 m•s-1 to 0.12 m•s-1. These values were lower than the minimum air velocity recommended. The main reasons for very low air velocity in the horse stable was incorrect location and the wrong design solutions, among which the most important were: the lack of ventilation aparatures and abnormal direction of opening windows ...