Objective: in order to evaluate the diagnostic value of the noninvasive method of the US-FNAC in the assessment of radiologically detected retroperitoneal masses and lymph nodes in gynecologic cancer. Methods: FNAC was performed under ultrasound guidance on 92 patients suspected of having retroperitoneal masses and lymph nodes. Cytologic examination was performed after staining smears with the haematoxylin and eosin method. In addition, The FNAC diagnosis was supported by examining cell blocks. Clinical data were retrieved from the medical records and all cytological specimens were reviewed. In metastatic and recurrent cases, the cytologic findings were correlated with the histology of the primary tumor and were compared with surgical pathology and core needle biopsy pathology. Results: A satisfactory sampling was obtained in 91.3% of punctures, and a cytological diagnosis was made in 90.2%. The size of the lymph nodes punctured was less than 20 mm in 62.1% (36/58). This test has a sensitivity of 88.9%, specificity of 100%, positive predictive value of 100%, negative predictive value of 55%, and accuracy of 90.2%. Five patients presented complications: pain. Conclusion: The fine needle aspiration technique has excellent positive predictive value and low complication. FNAC, as the valuable investigation, is not only useful in the diagnosis of retroperitoneal masses and lymph nodes in gynecologic oncology but can also help in choosing appropriate clinical management. Judging from our experience, FNAC can be added in follow-up in selected patients in whom the cytological identification of such masses and nodes is significant for the patient’s treatment.