Aim: The aim of the article was to present the issue of violence taking place in the basic social group, which is the family, in the form of incestuous sexual relations. The development of criminal liability for a given crime was mentioned. Various penal codifications in Poland were taken into account, including the Penal Code of 1932 and 1969. The results obtained showed the practical legal classification of an event that meets the statutory criteria of the crime of incest. The presented text is intended to provide a deeper analysis of the discussed phenomenon. Methods: The individual case method and examination of documents, i.e. court files. Results: The issue of incest, which was analyzed in the above research case, allows for drawing conclusions in terms of criteria such as: explaining the essence of the crime specified in Art. 201 of the Penal Code, the legal characteristics of the prohibited act specified in Art. 201 of the Penal Code and a discussion of the consequences of incestuous sexual intercourse for the family, especially the child, and the forms of assistance. As a result of a thorough consideration of the case by one of the District Courts in Poland, it was necessary to change the legal classification of the act charged against the accused. It should be noted that the amendment to the Penal Code, introduced by the Act of November 5, 2009, extended the qualified type of rape to include rape of an ascendant, descendant, adoptee, brother or sister. When imposing a sentence on the accused, apart from the circumstances that were directly related to the crimes he committed, the court also took into account the fact that the accused did not understand his behavior and did not feel any remorse for it.Coclusion: The research presented in the article below constitutes a way of learning about the crime of incest, which not only allows for expanding knowledge on this subject, but also provides practical guidelines for the legal classification of an act that meets the statutory features of the prohibited act in question. From the point of view of a criminologist and a pedagogue, practice is an important point to perform one's profession correctly. The research constitutes a section of scientific research on: "criminal law and criminological characteristics of the crime of incest (Article 201 of the Penal Code). However, I think that this fragment can be a reason to reflect on the issue of incest and how effective help can be provided to children who are direct or indirect victims of incestuous sexual intercourse.Oryginality: both the research conducted and the content obtained from it, as well as the remaining content of the study based on current premises and legal acts. Keyword: violence, incest, family, safety, crime, sexual intercourse, research case