Based on the revision of archival data by M.F. Kozyreva (1947–1949) and their modern reinterpretation, the paleoecological evolution of the Maikop Basin on the Kerch Peninsula sector during the Late Kerleutian–Tarkhanian (late Oligocene–Middle Miocene) was reconstructed using benthic foraminifera. Presence/absence data were analysed using Jaccard cluster analysis, taxa richness (S), and morphogroup analysis of agglutinated taxa, which allowed for the reconstruction of the temporal evolution of benthic foraminiferal assemblages, associated bottom-water environmental changes, and four successive phases of ecosystem transformation at local and basin-wide scales. The initial phase (Late Kerleutian–early Sakaraulian) was characterised by persistent agglutinated assemblages under relatively stable bathyal conditions, with recurrent Bathysiphon crises associated with reduced bottom-water circulation. The late Sakaraulian records the first calcareous inversion and local ecological restructuring within the existing bathyal basin. The Kotsakhurian records the regional ecological crisis, which is expressed by the widespread occurrence of monospecific Saccammina zuramakensis assemblages under hydrochemical instability. The Tarkhanian records a second calcareous inversion that is fundamentally different from the Sakaraulian event. It reflects basin shallowing toward outer sublittoral settings, increased marine connectivity, faunal renewal, and improved bottom-water oxygenation, while the characteristic Maikop-type of sedimentation was still maintained. These results demonstrate that, during the Late Kerleutian–Tarkhanian evolution of the Maikop Basin on the Kerch Peninsula sector, both local and regional environmental reorganisations elicited a recurrent pattern of benthic assemblage response, which is characterised by ecological crises followed by renewal.