Anemia, leukocytosis, thrombocytosis and other para neo plastic disorders have been seen in numerous malignancies especially in advanced stages. We studied the preoperational leukocytosis and thrombocytosis and clinical outcomes in patients with epithelial ovarian cancer. This study was carried out as a prospective cohort at the gynecology oncology department of Valiasr ward of Imam Hospital of Tehran university of Iran. The blood cells profile, post operational complications and overall survival have been investigated. The demographic characteristic and information concerning to specifications of ovarian cancer histopathologically, count of preoperational blood cells, post operational complications occurring after 30 days of surgery, recurrence and metastasize of disease during a year after surgery were investigated. Preoperational leukocytosis was associated with higher stage and grade and superficial and deep wound infections. Preoperational leukocytosis was associated with higher mortality rate and lower overall survival too. Further studies must pay attention to association between blood cells parameters and prediction of response to treatment option selected in epithelial ovarian cancer for choosing patients who are most profits of neo adjuvant chemotherapy.