One of the most important problems facing the government in Iran is insufficient government tax income and low share of this income in the government budget. Furthermore, according to the available evidence, this phenomenon is growing; so investigating effects of business climate indicators as one of the most important factors in the tax system is essential. Accordingly, with using PLS, and panel data in XLSTAT and Eviews software, the most important influential factors on direct and indirect taxes among the 30 business climate indicators are reviewed. Based on PLS method, between 30 reviewed indicators, five indexes of the multiplicity of taxes, assets transaction cost, the overall rate of taxes, import duties and charges have the highest contribution in the collection of direct and indirect taxes. Then, in separated panels, effects of selected indicators on the collection of direct and indirect taxes are estimated in the different provinces. Results of the panel data estimation on indirect taxes reflect the fact that, the variables of overall rate of taxes (74 hundredths), the cost of imports (22 hundredths), transaction costs of assets (0.5 hundredths); multiplicity of taxes (5 hundredths) and time to pay taxes (0.5 hundredths) have  larger impacts on the collection of indirect taxes. In the case of direct taxes, the overall rate of taxes and duties (30 hundredths), cost per transaction per asset (11 hundredths); the multiplicity of taxes (1.5 hundredths) and the cost of imports (one hundredth) have greater impacts. According to these results, the overall tax rate and duties are the most important factor influencing on the collection of direct and indirect taxes. Price variables, in other words, affect the collection of direct and indirect taxes in the country more than actual variables, which is because of low size of supply of services and products and a high share of the non-official economy of the national economy.