The article examines the institutional and functional elements of the mechanism of ensuring the state financial policy of sustainable development in Ukraine and in the world. It is determined that among the institutional components of the mechanism of the public financial policy of sustainable development, the institutions that carry out the process of control over financial resources play a special role. A special role is played by: the United Nations (a place where global challenges can be addressed), the Organization for Economic Co-operation and Development (in financing development), the European Union (in the mechanism for improving the sustainable development financial policy). It is researched that the basis of the mechanism of ensuring the state financial policy of sustainable development points to the strategic tasks of the state, which ensure the implementation of specific measures of the state financial policy of sustainable development (functional), which are necessary in the next few years to strengthen the development processes along with the estimated amount of necessary financial resources. Based on the analysis of the current state of financial policy adherence to the principles and objectives of sustainable development, the stages at which the country's economy is located, proposals are made for further reform. Since maintaining a sustainable fiscal policy is one of the country's top priorities, financial operations related to banking processes should be improved accordingly. An indicator of the achievement of global goals in the provision of the SFSD should be the elimination of extreme forms of poverty, the provision of quality education and access to energy sources. It is noted that in order to improve the financial policy of sustainable development, it is imperative to use all available means to ensure repayment of the credits with the minimum expenses of taxpayers. In order to increase the level of financial policy, we propose to pay more attention to one of the goals of the development of the National Bank of Ukraine - financial inclusion. Measures are proposed to increase the level of financial inclusivity. Proposals have been formulated that allow implementing the principle of joint responsibility of society and the state in the field of sustainable development, aimed at еnvironmentalization the economy, lawmaking and can be an expression of responsible representative state governance administration and contribute to the creation of an ecological state.