Abstract: The purpose of the study is to identify the key legal financial framework for regulating the contract system for the procurement of goods, works and services for public needs. The scientific novelty of the study lies in the fact that it not only substantiates the legal financial basis for regulating the contractual system, but also formulates the limits of the relevant regulation. At the same time, it was concluded that the legal financial regulation of the contract system is (and should be) limited, concentrating purely on the sphere of power and property legal relations of a public nature that arise and are implemented within the framework of the financial activities of the state and are associated with the formation, distribution and using state centralized funds. However, despite the presence of the above-mentioned limits of the legal financial regulation of the contract system, it is the financial and legal framework that acts as the basis of the contract system, since they mediate the correlation between the budget and procurement processes in the framework of achieving a single goal - the effective satisfaction of public needs while optimally spending budget funds.