The present paper discusses the issue of criminal responsibility of a physician for an omission. In the light of the applicable provision of the Penal Code of 1997, the criminal-law evaluation of an omission to provide medical aid by a physician in the presence of a risk to life or health of a person is two-directional. First, such behavior may constitute the formal crime of not providing aid, under art. 162 (1) of the Penal Code. Secondly, an omission to provide treatment may meet the criteria of a consequential crime committed by omission, directed against the life or health of a person, if it found that in the specific circumstances the physician had a special legal duty to prevent the consequence. Based on the literature, it was concluded that the matters of understanding of the special legal duty to prevent a consequence and of the sources of the guarantor's duty in the Polish criminal law raise numerous doubts. The authors illustrated the principles of criminal responsibility of physicians for criminal omissions in connection with their professional practice using, as case studies, two cases in which enforceable verdicts were issued.