The article is devoted to the analysis of the main European and domestic legal acts in the field of advertising, in particular, that of unfair advertising. In the course of the research, a short excursion was made to the practice of the Antimonopoly Committee of Ukraine regarding the implementation of measures of state control over compliance with the legislation on the protection of economic competition in advertising activities.The modern consumer has the right to receive reliable, necessary, accessible, timely information about the product, which gives him the opportunity to make a conscious choice in his favor. Any misuse of filling an advertising message with «defective» information results in a violation of current legislation and entails liability. However, in the conditions of information and technical evolution, there are more and more various forms of unfair competition in the field of advertising, which require an appropriate response.The definition of «unfair advertising» used by the Ukrainian legislator is currently too broad and does not contain clear criteria for determining the defectiveness of an advertising message and the qualification of its unfairness. Instead, the provisions of competition law contain clear indications of misleading information. In connection with this, in cases of inclusion of misleading information in the substantive component of advertising, there is a simultaneous violation of the Laws of Ukraine «On Protection from Unfair Competition» and «On Advertising».It has been established that domestic legislation is currently approaching European standards, but there is an urgent need to formulate clear criteria for determining the inauthenticity of advertising in order to eliminate gaps in the activities of advertising business entities and reduce potential opportunities for their abuse.