Behring received his medical degree in 1878 from the Friedrich-Wilhelms-Institut, the Prussian army's medical college, in Berlin. After serving 10 years with the Army Medical Corps, he became an assistant (1889) at the Institute for Hygiene, Berlin, where Robert Koch (Koch, Robert) was director. There, with the Japanese bacteriologist Kitasato Shibasaburo, he showed that it was possible to provide an animal with passive immunity (immune system) against tetanus by injecting (immunization) it with the blood serum of another animal infected with the disease. Behring applied this antitoxin (a term he and Kitasato originated) technique to achieve immunity against diphtheria. Administration of diphtheria antitoxin, developed with Paul Ehrlich (Ehrlich, Paul) and first successfully marketed in 1892, became a routine part of the treatment of the disease.

Behring taught at Halle (1894) and in 1895 moved on to become director of the Institute of Hygiene at the Philipps University of Marburg. He became financially involved with the Farbwerke Meister, Lucius und Brüning in Höchst, a dye works that provided laboratories for his research, which included studies of tuberculosis. His writings include Die praktischen Ziele der Blutserumtherapie (1892; “The Practical Goals of Blood Serum Therapy”).