One of the elements of implemented in Poland traffic control systems is module of priorities for public transport. Essence of working priority and the basic indicators of its effectiveness were presented. Among methods for testing the effectiveness of the priority, there has been distinguished economic and simulation approach. An example of priority research based on simulation of chosen street in Bydgoszcz was shown, using Vissim simulation environment. Developed simulation model, its connection to the control system, adopted detection system and 4 tested control strategies were also described. Then, the simulation and its results were presented. In results discussion they were compared in terms of adopted control strategies. In summary, possibility of a future study extension was also indicated.