Josef Heinrich Mattauch (born 21.12.1895) is an Austrian physicist and a member of the Austrian Academy of Sciences. He graduated from the University of Vienna (1920). In 1920 — 39 he worked at the University of Vienna and from 1939 at the Institute of Chemistry in Mainz (director in 1947-65). His work is in the field of nuclear physics and spectroscopy. He studied the binding energy of nuclei, establishing its dependence on even and odd values of the atomic number. He determined (1925) the magnitude of the charge of the electron (4.76*10-10 electrostatic units). He formulated the rule of the instability of isobars (1934). He improved the mass spectrometer (the Mattauch — Herzog mass spectrometer). He did much for the development of mass spectroscopy.