After an overview of the historical development of criminal biology from antiquity through the positivism of the 19th century to the eugenics movement at the beginning of the 20th century, this work presents modern criminal biological research and theories. In addition to genetic, sociobiological, and hormonal approaches, current investigations in the fields of psychophysiology, neuropsychology, and brain imaging are particularly explained. It becomes clear that modern criminal biological research is characterized today by its diversity and interdisciplinarity. This is especially evident in the numerous studies on the interaction of various social and biological factors.