While sentinel lymph node biopsy (SLN) is a highly accurate and well-tolerated procedure for patients with cutaneous melanoma, the role of the completion lymph node dissection (CLND) for patients with positive SLN biopsy remains unknown. This study aimed to look at the prognostic value of a positive nonsentinel lymph node (NSLN). A prospectively maintained database identified 222 patients with cutaneous melanoma and a positive SLN biopsy, without evidence of distant disease. All of these patients underwent CLND, and 37 patients (17%) had positive NSLN. With median follow-up of 33 months, patients with negative NSLN had median survival of 104 months, while patients with positive NSLN had median survival of 36 months (p < 0.001). There were no survivors in the patients with positive NSLN beyond 6 years. When patients with an equal number of positive nodes were analyzed, the presence of a positive NSLN was still associated with worse melanoma-specific survival (66 months for NSLN- versus 34 months for NSLN+, p = 0.04). While increasing age, tumor thickness, and male sex were associated with an increased risk of death on multivariate analysis, a positive NSLN was the most important predictor of survival (hazard ratio 2.5). We conclude that positive NSLN is an independent predictor of disease-specific survival in patients with cutaneous melanoma.