Tax systems of foreign countries, loopholes in tax systems, tax rates are reflected in the article. A wide review of the tax systems and tax rates of foreign countries was conducted, and a comparative analysis was made with the tax system and tax rates of the Republic of Azerbaijan. The tax system affects every moment of the world’s population. Not only in the past, but also in modern times, taxes have been one of the integral parts of human life. Whether the tax rates are high or low, taxes also help to improve the welfare of the people of the country. Despite the high tax rates in some countries of the world, the information about the high welfare of the population is one of the points of special attention in the article. The existence of different tax systems in the countries of the world and in our republic, the different tax rates and the effect of the applied tax rates on the welfare of the population are the characteristic aspects of this article. Purpose: The purpose of the article is to study the tax system of foreign countries and conduct a comparative analysis of them with the tax system of the Republic of Azerbaijan. Methodology: The method of induction, deduction, research and analysis was used in the research work. The result of the research: As a result, the important role of the tax system in human life has been proven once again. Taking into account the state of the country’s economy, the tax policy, which is properly developed on the basis of scientific concepts, serves to improve the welfare of the people. The tax system also creates conditions for the population to engage in legal economic activity. Keywords: tax system, tax rates, economic efficiency, local taxes, income tax