Taxes are exclusively cash benefits, they are forced and non-refundable, which means that there is no counteraction for them. Taxes are also the most important income of every state. The modern world has accepted the payment of taxes as inevitable because it largely allows for the normal functioning of the state. Very often they are the subject of discussions because of their easy variability, and it is for this reason that the need arises for their further research and study of the effects they have. The topic of this paper is taxes, with special reference to income tax, which is an essential component of the tax systems of all modern countries. The paper discusses the basic determinants of income tax, its objectives, characteristics, effects of taxation, the procedure for determining the income tax liability, corporate taxpayers, and tax rates. Then, the similarities and differences of corporate income tax in the Republic of Croatia and neighboring countries, Slovenia and Serbia, will be compared and analyzed, with the aim of comparing the tax burden in the Republic of Croatia and neighboring countries. In addition to books, which are the main source of data on this topic, electronic databases such as Hrčak were used as a source, as well as various websites on which specialized content in this area is published.