The topic of this paper is profit tax. Taxes are the most important and most abundant type of government revenues. Taxation system makes the totality of all forms of taxation. Tax system in the Croatia represents a modern system, compliant with the guidelines of the European Union. Corporate Income Tax is regulated by regulations respectively the Law on corporate Income Tax and rule book of corporate Income Tax. Also, there are a number of special laws and other regulations which separately regulates vorious forms of tax and the rights and duties of taxpayers. Profit tax is considered as a product of the 20th century and it is in almost all taxation systems in the world. In modern countries, corporate income tax, as one of the direct tax form has a greater significance, while in Croatia it has lower significance, because of the orientation of the Croatian tax system to indirect tax forms. Various income tax reforms have been taken in Croatia in order to achieve a certain upcoming fiscal and economic effects, but the economic effects have not been achieved, at least not so far as they were expected. The most significant tax form filling Croatian government budget is a value-added tax and various excises, followed by income tax, while profit tax has no large impact.