The article shortly describes the life path of Erwin Chargaff, one of the most famous figures in the history of molecular biology and genetics. Chargaff was born in Chernivtsi (Austria-Hungary, now Ukraine) but during the First World War his family was forced to move to Vienna. After graduating from the University of Vienna, Chargaff worked in Berlin, where he studied bacterial lipids. Due to Nazis coming to power in Germany, Chargaff moved to Paris and later (1935) emigrated to the USA and obtained a position at Columbia University, where he initially investigated the role of phospholipids in blood clotting. In 1944, applying novel methods Chargaff initiated intensive investigation of the chemical composition of nucleic acids from taxonomically distant species and established two rules which were later named after him. The first Chargaff‘s rule provided a significant support to Watson and Crick in construction of their double helical DNA model. The explosion of atomic bombs over Hiroshima and Nagasaki forced Chargaff to think about the moral responsibility of researchers and science to mankind. He begins to raise these issues in the press and manifests himself as a talented journalist, who criticized the bureaucratization of science and its transformation into a way of earning money. Despite decades of life in America, spiritually Erwin Chargaff always remained a European, who never forgot his roots and always remembered his native land.