Lymph node metastases are common in papillary thyroid cancer (PTC), yet the impact of nodal metastases on survival remains unclear. Lymph node density (LND) is the ratio between the number of positive lymph nodes excised and the total number of excised lymph nodes. Lymph node density has been suggested as a prognostic factor in pancreatic, gastric, colon and oral cavity cancers. In this study authors evaluated the prognostic role of LND in PTC. Medical records of 2542 patients with PTC were reviewed. The 10-year disease-specific survival rate was 98% for patients with LND of 0.19 or less, compared with 90% for those with LND greater than 0.19. This single-institute study demonstrates the reproducibility of LND as a predictor of outcomes in PTC. Lymph node density can potentially assist in identifying patients with poorer survival who may benefit from more aggressive adjuvant therapy.