Polycystic ovary syndrome (PCOS) is the most common endocrine-related reproductive disorder in women of reproductive age, accompanied by both the impairment of female fecundity and a risk of metabolic disorders. PCOS is emphasized as a worldwide concern due to its unknown etiology and lack of specific medications. The current study aimed to evaluate the effects of L-tartaric acid, an abundantly occurring compound in fruits, on the histostereological and hormonal changes caused by PCOS. Forty adult Sprague Dawley rats were randomly divided into four groups including controls (no intervention), Tartaric acid (40mg/Kg/day from day 21 onwards for 39 days), PCOS (21 days letrozole and then normal saline orally for 39 days), and PCOS + Tartaric acid. After treatments, the ovarian histostereological analysis as well as the level of reproductive hormones including luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, progesterone, and testosterone was measured. PCOS caused a significant decrease in the number of unilaminar, multilaminar, antral, and graafian follicles and increased follicular atresia (p-value < 0.001). Moreover, the weight and volume of ovarian tissue and related structures including cortex, medulla, and cysts increased significantly (p-value < 0.0001). However, corpus luteum volume was significantly decreased (p-value < 0.001). Although significant differences were found in some parameters with the control group (p-value < 0.05), the administration of tartaric acid restored the pathological effects of PCOS on the ovarian histostructure. Furthermore, tartaric acid improved the serum levels of LH, estradiol, progesterone, and testosterone (p-value < 0.05). The obtained findings may suggest tartaric acid as a novel strategy for PCOS management, although further studies are necessary.