Violence undermines an individual’s personal freedom, forces them to behave against their will, and thus endangers the life and health of the individual and of a social group such as the family. The right to protection against domestic violence is one of the duties of a state whose failure to act can be considered a violation of human rights. In fulfilling this obligation, Poland has established a system for preventing domestic violence. An important element is the Police, which was the first to implement the procedure of counteracting domestic violence called „Blue Card”. It happened already in 1998, when the Chief Police Officer issued an order, which specified the way in which police officers would perform their tasks related to preventing domestic violence, and also introduced Blue Card prints for official use. Then, on the basis of the aforementioned Act, the Regulation of the Council of Ministers of 13 September 2011 on the „Blue Card” procedure and on the model forms of the „Blue Card” was issued. The above mentioned legal acts impose on the Police certain tasks in the system of counteracting domestic violence. The paper is an attempt to answer the question: What role does the Police play in the system of preventing violence within the family?