Beef production is one of the most important segments of the cattle industry. In most European countries, the main source of beef is represented by intensively fattened bulls of beef and dairy breeds, or their crossbreds. They contribute approximately 50% to the overall beef production in European Union as well as in the Czech Republic (CR). Profitability of fattening operations is a fundamental prerequisite for sustainability and further growth of domestic beef production. Therefore, the objectives of this study were to evaluate the economic efficiency of fattening bull operations in the CR, to determine minimum profitability requirements, and to perform a sensitivity analysis. From 2013 to 2016, input data were annually collected from 16 to 18 farm operations located in different regions of the CR using a questionnaire.