The paper examines the classification of subjects of financial law; it is proposed that, along with public and private entities, they should also include para-public entities. The authors suggest defining para-public entities as authorized legal entities established by law for exercising public administration, providing public services and performing other public functions. This category is based on the need to implement public interests in modern conditions. The author analyses foreign experience concerning delegation of government powers to para-public organizations in Brazil and the United Kingdom. The author has examined the legal status of non-state organizations, performing public functions. It is proposed to use a contractual method of regulation of financial relations, including the application of standard form contracts (public contracts) in financial law. The introduction of the institution of contract, autonomy, financial independence and self-government into the mechanism of public administration will help to solve a number of key problems of financial activity. At the same time, it is necessary to develop the institution of standard form contracts (public contracts) already existing in financial law, by which we propose to refer to the agreement concluded in the established form for public purposes by two or more entities, one of which is a public authority, and aimed at the realization of the public interest.