The aim of this article is to provide a theoretical definition of the financial aspect of liquidity of enterprises, to improve the classification of the types of liquidity and determine its functions. The subject of the study is to consider the problematic issues of classification of the types of liquidity, which are manifested in the object or subject in the form of a three-level hierarchical structure at the macro- and micro levels of management and the interconnections between them. The theoretical foundations of financial and economic categories of "liquidity" are presented in the works of A. Marshall, A. Montchrestien, W. Petty, A. Smith, W. Stafford and others. J Keynes and K. Marx made a significant contribution to the development of this theory.  At the present stage, the works of many Ukrainian and foreign economists are devoted to consideration the enterprises' liquidity: S. Brue, S. Myers, K. McConnell, I. Fischer, M. Friedman, J. Hicks, P. Laiko, L. Lakhtionova, E. Nikbacht and A. Gropelli, A. Podderyogin, G. Savitskaya and others. However, these issues have not been sufficiently investigated in the published scientific works. Financial stability is the basis of every enterprise in a market economy. In this process, the priority is to ensure its liquidity. Many scientific works of both foreign and Ukrainian scientists are devoted to the study of various aspects of liquidity. However, so far there is no clearly defined system of theoretical conclusions on the assessment of the enterprises' liquidity. The questions about the place and role of liquidity in the financial management of the enterprise remain undisclosed or debatable, the classification of its types needs to be improved. This has a negative impact on the possibilities for efficient liquidity management. Therefore, the problem of ensuring liquidity in a market economy remains relevant

liquidity; solvency; liquidity functions; financial stability; classification; current assets; liquidity object; liquidity subject