The relevance of the issue under study in this article is due to the rapid development of social relations, which leads to the constant emergence of new types of transactions, their formalization and regulation. A transaction is a basic category for the regulation of civil legal relations, including such a type of transaction such as a fraudulent transaction. A comprehensive study of the institute of fraudulent transactions in Ukraine will be a significant basis for further improvement of the current not only civil legislation, but also administrative legislation, and will unify the judicial practice of applying legislation on fraudulent transactions. The following methods were used in the study of scientific cognition, such as: systemic and structural; comparative; and the method of analysis. Based on the analysis of the current legislation of Ukraine in the field of application of fraudulent transactions the author emphasizes that there is no clear definition of a fraudulent transaction, its features, and the consequences of its conclusion. However, the absence of a regulatory definition of a fraudulent transaction in the current legislation of Ukraine causes conflicts in court decisions, as evidenced by the analysis of court practice, including that of the Supreme Court of Ukraine analysis of court practice, including that of the Supreme Court. This legislative gap should be regulated, since the legal regulation of fraudulent transactions in Ukraine plays an important role in the administration of justice and protection of participants whose interests are violated by such transactions. The author reviews of the key categories of this scientific article, including “legal regulation” “fraudulence”, ‘fraudulent transaction’. The author proposes to define a fraudulent transaction as to understand the action of a debtor or a party to a legal relationship which exists at the time of or has a high probability of becoming a party to a legal relationship, which can be expressed by both active and passive legal behavior aimed at avoidance of undesirable consequences for the debtor or a person (probable party to the legal relationship) Consequences aimed at avoiding civil liability, non-occurrence of undesirable civil status, or obtaining a benefit in an unfair manner. The author concludes that it is necessary to improve the legal regulation of a fraudulent transaction in Ukraine in the context of defining its essence, features essential terms of the contract, and legal consequences of its application.