Polycystic ovary syndrome (PCOS) or Stein Leventhal Syndrome is an inflammatory metabolic disorder resulting in ovarian dysregulation and dysfunction leading to infertility in 7-20% of women globally. Present experimental study was designed to evaluate the therapeutic effects of medicinal plant (Cinnamomum zeylanicum) using chitosan nanoparticles on the hormonal profile and ovaries of PCOS-induced mice. Methanolic extract of Cinnamomum zeylanicum was used to synthesize chitosan nanoparticles (CNPs) by ionic gelatin method. The synthesized particles were characterized by FTIR and XRD analysis. Experimental mice were given an intraperitoneal injection of 2 mg/Kg Estradiol valerate in 0.1 ml corn oil to induce PCOS. Results have demonstrated a protective effect of biomolecule-coated chitosan nanoparticles (CNPs) on the improved ovulatory function of PCOS-induced mice. Mice treated with CNPs showed the recovery of the estrous cycle and gonadotropin (FSH, LH) hormones. The FSH titre regain in CZCNPH from 0.58 to 0.75 mIU/ml, similarly, LH levels were reduced from 0.65 to 0.53 mIU/ml. The biomolecules loaded CNPs showed the formation of the oocyte, the formation of zona pellucida, zona granulosa and the dissolution of cysts in PCOS mice. Histomor[hometric analysis showed high diameter of oocytes in CZCNPH group. We conclude that the biomolecules loaded CNPs can effectively be used to treat PCOS as compared to synthetic drugs.