The study seeks to define the group of people protected under the provisions on genocide both in the Polish criminal law and international criminal law. The provisions of the Convention of 9 December 1948 on the Prevention and Punishment of the Crime of Genocide, the Rome Statute of the International Criminal Court and the Statutes of the International Tribunal for the Prosecution of Persons Responsible for Serious Violations of International Humanitarian Law Committed in the Territory of the Former Yugoslavia and the International Criminal Tribunal for Rwanda contain a very similar definition of genocide. Killings and other acts listed in that legislation, committed in order to exterminate all or part of national, ethnic, racial or religious groups as such are prohibited as genocide. Similar conduct was prohibited in the provision of Article 118 of the Polish Penal Code. However, the protected group has been identified differently. It has been defined much more widely in Polish criminal law than in international law. A perpetrator of genocide acts with the purpose to exterminate all or part of a national, ethnic, racial, political or religious group or a group with a specific worldview. There are two important differences: the first is that international law acts prohibit intentional conduct while Article 118 prohibits purposeful conduct. The second difference is a much narrower definition of groups protected by international regulations. They do not protect a political group and a group with a certain worldview. This study analyses the consequences of this distinction, in particular the possibility of classifying the conduct aiming against a political group and a group with a particular worldview.