The thesis analyzes and compares tax burden on employees in the Czech Republic and Belgium. The first part summarizes the tax systems of the two countries, and describes how to proceed in the calculation of their tax burden. The second part deals with the comparison of effective tax rates for different types of taxpayers. The third part discusses the tax progressivity in terms of local progressivity, which is measured by using provided intervals and determines for which income categories is the progressivity most important. Lorenz curve in the last part shows graphically global tax progressivity and redistribution of income in society. The Gini coefficient measures it. Final evaluation highlights the important ties between the two countries, compares with other countries of the European Union and its future development especially in the area of taxation of wages.