The analysis of the development of approaches to assessing the financial security of an enterprise shows that there is no single methodology that confirms that certain problems exist and need to be solved. The working hypothesis adopted in the study is that financial threats are the factors that most destabilize financial security of an enterprise. The purpose of this article is to clarify the nature of the concepts of financial security of an enterprise and financial security management and to develop a methodological approach to assessing the financial security of an enterprise in a changing external environment. The methods used in the study of specific tasks were comparison and systematization; graphical; abstract and logical methods. The practical significance of the research results is that they substantiate the model for assessing financial security, which is an integral part of the overall enterprise management process. A model and algorithm for the formation and implementation of a strategy for ensuring the financial security of an enterprise are suggested.