Taxes are fundamental source of revenues for every economy and the most important segment of fiscal policy. The essence of tax forms is manifested through need to collect funds necessary to finance public expenditures and meet public needs. The paper explains the theoretical concept of optimal taxation from aspect of measuring tax burden, basic tax principles and Lafer curve. Likewise, optimal tax structure is explained by Ramsey rule. The paper should contribute to expansion of theoretical opus on optimal taxation problem and points to importance of an optimal tax structure which will be in the function of improving macroeconomic framework of a country.