This article attempts to study the fundamental problems in implementing (realization) the principle of transparency (openness) budgets of the Russian Federation. The sources analyzed in the article are the RF budgetary code, federal laws, normative acts of the Finance Ministry as well as text books and Internet resources. The author seeks to trace the implementation of the legal mechanism of this principle in terms of results-oriented fiscal policy as well as to compare it with foreign ways and approaches of ensuring the principle of transparency (openness) of budgets. The article shows the connection between the transparency of budgets and democratic principles, a clear distribution of functions among state bodies, reliability, efficiency and comparability of the data on profits and expenses of the state, a stable interest of the public in Russia and abroad to the involvement in the budgetary process. The article stresses that the transparency relates not only to budgets and the reports on their implementation but the drafts of budgetary laws and state procurement. The transparency principle has exceptions in Russia, which is shown in the example of the federal budget classified items. The foreign experience of the transparent administration of public finances has been studied on the example of Porto Alegre municipality  (Brazil). The positive results of the administration were seen in the eradication ofinappropriate use of funds, increase in the confidence of ordinary citizens to public administration. Besides, collection of tax became more consistent. The publication shows the serious role played by the codes of professional behavior to develop the budget transparency principle. However, the author expresses concern that the transparency principle was not observed when these codes were being developed having resulted from the absence of their public discussion.