Background: Peritoneal washing cytology (PWC) that shows the microscopic intra-peritoneal spread of gynaecologic cancers is not used in staging but is known as prognostic factor and effective in planning the intensity of the therapy. False negative or false positive results clearly affect the ability to make the best decision for therapy. In this study we assessed levels of tumour markers, carcinoembryonic antigen (CEA), cancer antigen 125 (CA-125) and carbohydrate antigen (CA19-9), in peritoneal washing fluid to establish any possible contribution to the peritoneal washing cytology in patients operated for gynaecologic cancer. Materials and Methods: Preoperative tumour markers were studied in serum of blood samples obtained from the patients for preoperative evaluation of a gynaecologic operation. In the same group peritoneal tumour markers were studied in the washing fluid obtained for intraoperative cytological evaluation. Results: This study included a total of 94 patients, 62 with malignant and 32 with benign histopathology. The sensitivity of the cytological examination was found to be 21% with a specificity of 100%. When evaluated with CEA the sensitivity of the cytological examination has increased to 37%. Conclusions: In addition to examination of PWC, the level of CEA, a tumour marker, in peritoneal washing fluid can make a diagnostic contribution. Determining the level of CEA in peritoneal washing fluid will be useful in the management of gynaecologic cancers.