The aim of the current research is to analyze the legislative definition of completed crime, to consider the theoretical issues of the comprehension of completed crimes, to define related problems and offer solutions. The methods applied in the research included: analysis, synthesis, comparison, system method. The result achieved can be summed as follows. The paper considers the legislative definition of completed crime and includes different interpretations of this phenomenon. It identifies the disadvantages of existing interpretations and shows possible solutions. The author mentions three main disadvantages of the legislative definition of a completed crime. First, it is the imperfection of the legislative technique and the location of the norm in the chapter which is dedicated to an uncompleted crime. Second, the legislative definition doesn’t allow one to distinguish between completed and uncompleted crimes. Third, there is no indication of the legal nature of a completed crime. The author criticizes the fact that the term “completed crime” is applied only to crimes which are completed with the direct intention. The paper features the author's own definition of a completed crime, which is based on the achievement of the statutory moment of crime completion.