Objective To assess the relationship between benign gynaecological disorders and ovarian cancer (OC). Methods This retrospective observational study enrolled female patients with histologically-confirmed primary OC. Clinical and demographic data were collected using a questionnaire. Blood samples were analysed for tumour biomarker levels including cancer antigen (CA)-125, CA19-9, carcinoembryonic antigen, β human chorionic gonadotropin (β-hCG) and lactate dehydrogenase (LDH) using enzyme-linked immunosorbent assays. Results A total of 100 female patients were enrolled in the study. Of these, 44 patients had simple ovarian cysts (44%), 22 had uterine fibroids (22%), 15 had adenomyosis (15%), 13 had pelvic inflammatory disease (13%) and six had endometriosis (6%). There was a significant association between high grade serous OC histology with both benign ovarian and uterine diseases. There was a significant association between both adenomyosis and uterine fibroids and high grade OC. There was also a significant association between endometriosis and stages III/IV OC. With regard to tumour biomarkers, there was a significant association between β-hCG and LDH biomarkers and benign uterine tumours. Conclusion Benign gynaecological diseases are accompanied by the high risk of the development of OC. Common benign gynaecological diseases associated with OC were uterine fibroids and adenomyosis.