The present work was devoted to the comparative analysis of a4в2 nicotinic acetylcholine receptors (nAChRs) in learning/ memory processes during ovary cycle assessed in adult female rats. RJR-2403 (1.0 mg/kg, i.p.), a4в2 nAChRs agonist and mecamylamine (1.0 mg/kg, i.p.), a4в2 nAChRs antagonist were injected chronically during 14 days. The processes of learning/memory were assessed in different models of learning: passive avoidance performance and Morris water maze. Chronic RJR-2403 administration to female rats improved the passive avoidance performance in proestrous and estrous as compared to the control animals. Also, RJR-2403 restored spatial learning during proestrous phases in Morris water maze, and stimulated the dynamics of spatial learning during estrous phases. On the contrary, chronic mecamylamine administration impaired non-spatial, and especially, spatial learning in females during key phases of ovary cycle. The results of the study suggest positive effect of a4в2 nAChRs stimulation in learning/ memory processes during ovary cycle in the adult female rats. Key words: RJR-2403, mecamylamine, a4в2 nAChRs, learning, ovary cycle, female rats.