Backgroud: Amenorrhea and ovarian disorders are a common concern of women under the age of 40, a condition medically known as premature ovarian failure (POF). The incidence of POF among Egyptian women before the age of 40, is about 8% that exceeds the global incidence which is about 1%. Chemotherapeutic agents were linked to toxicity of ovarian tissues and disturbance of ovarian functions. Provision of a suitable protective agent with high efficacy, low side effects and cost is a major challenge in the field of oncofertility. Aim of the Study: Is to evaluate the mechanism of PRP treatment in induced ovarian failure due to cyclophosphamide. Materials and Methods: The present study was carried out on twenty-nine albino rats. Twenty-four adult female albino rats were used as the experimental group. Five age-matched healthy male albino rats were used to get the PRP. The twenty-four adult female albino rats were randomly assigned into three groups (control, group II: received cyclophosphamide, group III: received cyclophosphamide and PRP). Plasma estradiol and progesterone levels were measured on day 22 after cyclophosphamide treatment before experimental rats euthanasia. The rats were euthanized and ovaries were anatomically examined using dissecting stereomicroscope. Sections of the ovaries were prepared and examined histologically, immunohistochemicaly and using transmission electron microscope. Results: Cyclophosphamide treated groups showed signs of degeneration of follicles and oocyte and deterioration of ovarian functions. PRP treated group showed improved appearance of ovarian follicles and improved ovarian functions. Conclusion: PRP seems to have protective effects on ovarian tissues and functions and its concomitant use with cyclophosphamide helps to restore the ovarian tissues.