The article analyzes the reasons and motivation for some Soviet citizens’ desertion to Nazi Germany in the Great Patriotic War. The article is based on archival materials of criminal cases of the KGB of the USSR in the Belgorod region in relation to persons who in the period of temporary occupation of the region volunteered to the civil and repressive bodies established by the German invaders and their allies. It was found that the main reasons which prompted some Soviet citizens to serve for Nazi Germany were hatred of the Soviet regime, the desire to avenge their relatives and friends, the desire to curry favor with the occupation authorities, reckless and criminal propensities. It was stated that in the appointment for the chief of positions in repressive bodies (city, district police, gendarmerie) collaborationist organs of civil government (mayor, mayors, heads of departments, foremen) in the south-eastern districts of the Kursk region, the leadership of the German occupation authorities and intelligence authorities took into consideration the sincere desire to serve the interests of Nazi Germany.