The article examines the traditional institutions of military culture of the Circassians – military departure and departure for service. Departure for service was part of the universal system of replenishment of the ruling class of the feudal powers of Europe and Asia, into which the Circassian aristocracy had long been deeply integrated. This was favored by a well-deserved reputation in the military sphere, a highly effective and perfect system of military education, as well as the cultivation of the knightly idea and its components such as loyalty to the suzerain, nobility, aristocratic etiquette "uerk khabze". Departure for service was a purely feudal institution, with the appropriate completion within the framework of vassal-suzerain contractual relations. Departure for service was characteristic of the upper strata of the Circassian aristocracy; for all other classes of Circassian society, military otkhodnik (mercenary) was characteristic. The latter did not imply the conclusion of contractual relations, the establishment of vassal-suzerain relations and correspondingly – incorporation into the ruling class of the host countries. Departure for service and mercenary practices were among the basic and most characteristic institutions of the military culture of the Circassians. For a long time these institutions have played a significant role in the life of Circassian society, and their study has not only scientific and educational, but also practical value. The study of the institutions of military culture can contribute to the understanding of the historical-political and socio-economic processes that took place in the Central and Northwestern Caucasus during the Late Medieval and Early Modern Times.