The results of forensic medical investigations of 100 corpses of the persons who died from combined intoxication with two and more poisons are presented. They were compared with clinical observations and summarized uisng the methods of tanatogenetic analysis. The main variants of fatal combined poisoning and the underlying tanatogenetic mechanisms were categorized into cardiac (disturbances of rhythm and conductivity, progressive hypotension, flabby heart muscle, extensive fragmentation of cardiomyocytes), cerebral (coma and massive death of brainstem neurons), and pulmonary (of pneumonia- or pulmonary oedema-type with fibrin precipitation in the alveoli and formation of hyaline membranes). This classification was supplemented by a variety of combinations of the above variants with necrotic nephrosis and disseminated intravascular coagulation syndrome. It is concluded that the results of this study may be of use for forensic medical diagnostics of combined poisoning and the elucidation of the contribution of individual toxic substances to the fatal outcome bearing in mind the low informative value of the relevant forensic medical data.