Introduction: Sarcoidosis (SD) is considered to be a T-cell-driven disorder, but recent studies show also B-cells participation in SD (Musaelyan, 2018; Saussine, 2012). The aim was to determine the different subsets of memory B-cells in SD. Methods: A prospective comparative study was conducted in 2016-2018 with examination of patients with SD (n=37) and healthy control (HC) (n=35). 200 μL of whole blood were stained on surface with fluorochrome-conjugated monoclonal antibodies: anti-IgD Alexa Fluor 488 (clone IA6-2, isotype - Mouse IgG2a, κ), anti-CD38 PE (clone LS198-4-3, isotype - IgG1 Mouse). IgD, CD19 - BioLegend, Inc. (USA), CD38 - Beckman Coulter, Inc (USA). Sample acquisition was performed with a Navios flow cytometer (Beckman Coulter, Inc., USA). Supported by Russian Federation Government Grant (contract N14.W03.31.0009 of 13.02.2017). Results: The frequency of B cells in SD was significantly higher than in HC (14.48% (9.86; 17.29) vs 11.09% (8.52; 13.28), p=0.008). “Activated naive” Bm2 cells and pr