The aim of the study. The aim of the work was to investigate in vivo anticancer activity of cis- and trans-diadamanthylcarboxylates of dirhenium(III) alone and together with cisplatin in form of nanobins.Materials and methods. Model of tumor growth, Guerin’s carcinoma; intraperitoneal administration of cisplatin, dirhenium(III) compounds in liposomes and of binary liposomes, containing both cytostatics; volumes and final weights of tumors were measured.Results. In vivo antitumor properties of two dirhenium(III) dicarboxylates with 1-adamantanecarboxylic acid moieties as ligands with cis- (I) and trans- (II) orientation of the carboxylic groups around a cluster fragment alone and together with cisplatin were presented; an attempt to understand differences in a possible mechanism of anticancer activity of the substances were undertaken. Antiradical and DNA-binding properties of I and II were the matter of consideration.Conclusions. Cis- and trans- compounds of dirhenium I and II had close antitumor activity in vivo with a little bit superiority of the cis- analog. Mechanisms of anticancer activity of I and II are different and may also include monofunctional adduct formation and subsequent interstrand cross-linking for the II substance, formation of protein-DNA cross-links, etc.