The imbalances and the ongoing financial and economic crises that the economies of the rentier countries suffer from oblige those countries to search for the reasons for that and to indicate appropriate methods and solutions to address these imbalances, especially the financial deficit in their general budgets. Thus the study aims to measure and analyze the impact of oil revenues and other non-oil sources of income on sustainability indicators Finance in the countries of the Gulf Cooperation Council group. The study concluded that there is an inverse and significant relationship between total oil revenues as a percentage of the gross domestic product and financial sustainability. Which is expressed in the deficit and surplus of the general budget as a percentage of the gross domestic product and at a significant level less than (5%), meaning that the increase in total oil revenues by (1%)) will lead to a decrease in the public budget deficit by (-0.372%). And the existence of a direct and significant relationship between the total other revenues as a percentage of the gross domestic product and the general budget deficit and surplus as a percentage of the gross domestic product. The study recommends the need to find the necessary ways to increase non-oil imports, given that natural resources are depleted and limited, in addition to the nature of fluctuations in their prices, and to carry out structural reforms to diversify sources of income and create an environment that enables prosperity in non-oil production and export, which would contributes to reducing the vulnerability of public revenues to fluctuations, In order to restore the sustainability of fiscal policy, income sources should be diversified in the countries of the study sample, by activating all economic sectors that will lead to diversifying income, improving the level of competitiveness, and reducing the country's dependence on a depleted resource.