From a systematical study of German ticks resulted the occurrence of two tick species of the genus Dermacentor. D. marginatus is found to be widely spread in Southern Germany. Adults of the tick feed mainly on sheep. D. reticulatus is first described from Germany where the tick occurs endemic in a limited forest area on red deer. The two tick species are known from neighbouring countries of Germany in transmitting virus, rickettsiae, bacteriae and protozoa but are not yet well studied in Germany. Geiographical distribution and seasonal occurrence of D. marginatus indicates the role of the tick in the epidemiology of Q fever in Germany.