Objective: To determine the usefulness of the Sentinel Node (SN) in ovarian tumors. Method: 28 patients with ovarian tumor, who underwent gynecological laparotomy, injecting medial and lateral under the serosa isosulfan blue in the ligaments of the ovary and the pelvic infundibulum, with visualization of the SN in the retroperitoneum of the pelvic region and para-aortic, 15 minutes after dye injection. Results: Lymphatic drainage was unilateral. A total of 64 SN was identified, for an average of 2.3 SN per patient, SN was identified in 26/28 (92.9 %) of the cases (overall detection rate). The SN detection rate in the para-aortic region exclusively was 26/64 (40.6 %), only in the pelvic region 22/64 (34.4 %), and in both regions 16/64 (25 %). Sensitivity and Specificity ofthe SN was 100 %, without False Positive or Negative; with a Negative Predictive Value (NPV) and Positive Predictive Value (PPV) 100 %; 100 % effectiveness and 0 % diagnostic error. There were no complications. Conclusion: the under the serosa isosulfan blue infiltration technique is effective in identifying SN and, in turn, is useful in identifying lymph node metastases in the perioperative biopsy. It can be an effective tool to provide reliable information on lymph node status, eventually allowing replacement of routine lymphadenectomy in this group of patients.