Hemorrhagic fever with renal syndrome (HVRS) has been for decades a topical problem for healthcare systems of many countries in the Eurasian continent. Viruses triggering HVRS alongside with other related viruses (but not pathogenic to man) were discovered in 70-80-ies and formed a new genus Hantavirus of the Bunyaviridae family. The study results of a severe outbreak of the respiratory disease with the mortality rate of 60% (South-West of the USA, 1933) showed that hantaviruses were also among the causative agents. Later, the disease was designated as hantavirus cardio-pulmonary syndrome. By now, it has been established that hantaviruses are wide spread with different rodents being their carriers. The discussed viruses cause, in rodents, a chronic asymptomatic infection and are transferred, later, to man by the aerogenic path through excretions of infected animals. Studies of hantaviruses have been restricted for a long time due to their high pathogenicity (protection equipment not below than the P-3 level is needed), because of a lack of a laboratory model of infected animals and because of a low growth in cell cultures. With the rapid development and application of molecular biological techniques of the recent years, substantial progress has been made in studies of hantaviruses. Different aspects of hantavirus ecology, molecular biology, morphology, pathogenesis and diagnostics are discussed in the offered survey.