ABSTRACT This study investigated whether abemaciclib (ABE) administration had any adverse effects on ovarian and sex hormones in female rats, and the protective effect of curcumin. Forty female rats were equally divided into the sham control, DMSO, curcumin (CMN), ABE, and ABE+CMN groups. Pharmaceuticals were administered by gavage daily for 28 days. Serum sex hormones were measured in an autoanalyzer operating with a microparticle immunoassay method. In addition, histopathological examination and 8-OHdG expression were performed on the ovarian tissue. Progesterone and testosterone levels were significantly decreased, while estradiol levels were significantly increased, in the ABE group compared to the sham and DMSO groups. In addition, there were significant differences in sex hormone levels in the CMN and/or CMN+ABE groups compared to the ABE group. There was decreased expression of 8-OHdG in the ABE+CMN group compared to the ABE or CMN only groups. This study exhibited that ABE administration can adversely affect functions and histology of the ovarian tissue, but CMN therapy may be protective against the adverse effects on ovarian in ABE-induced rats.