This paper presents results of research on ammonia concentrations and emissions from a free stall barn to the atmosphere in the course of one year, with particular attention to the summer and winter periods. The rate of ammonia emissions was influenced by the amounts of ventilated air, which were the highest in summer period and lowest in winter. The obtained results were lower than the values provided by other authors, which points out the need for conducting further detailed studies on ammonia emissions from various types of free stall barns and cattle breeding systems.