The objective of the article is the scientific understanding of the problem of ensuring the right to medical care of a detainee or detained in custody within criminal proceedings, based on the experience of Ukraine and some foreign states, as well as the formation of conclusions and recommendations to resolve this problem. In the process of writing a scientific article, the authors have used general scientific, special and legal methods. Questionnaires - to interview respondents from among police officers of the National Police of Ukraine and lawyers. The analysis method made it possible to study the reasons that contribute to the existence of problems related to ensuring the right to medical care of a detainee or detained in custody within criminal proceedings of Ukraine. The methods of comparative law were used to identify shortcomings and controversial provisions of the criminal procedural legislation of Ukraine in comparison with the provisions of legal acts of some foreign states. The authors of the article have concluded about the need to supplement the Art. 42 of the Criminal Procedural Code of Ukraine with the norm stipulating the right of a detainee or detained in custody for appropriate medical care, including the free choice of a physician and an independent medical examination. The result of the legislative consolidation of the right to medical care of a detainee or detained in custody within criminal proceedings of Ukraine must be: 1) reduction of the number of facts of violation of human rights in the course of criminal proceedings, bringing the national Ukrainian criminal procedure legislation closer to the EU standards; 2) reduction of cases of abuse of the right to medical care during criminal proceedings by the person against whom it is carried out; 3) minimization of the possibility of satisfying claims filed with the ECHR against Ukraine regarding violations of the right to medical care.