The aims of this study were to clarify the distribution and spread pattern of metastatic nodes and to evaluate the importance of the number, ratio, and location of positive nodes in ampullary adenocarcinoma. We analyzed the clinicopathologic data and survival of 52 patients who received curative pancreatoduodenectomy for ampullary adenocarcinoma between June 1994 and May 2009. Metastatic lymph nodes were found in 32 (61.5%) patients. The median number of evaluated nodes and positive nodes were 26 (range 10-60) and two (range 1-15), respectively. The most commonly involved nodes were the posterior pancreaticoduodenal nodes (26 patients) followed by the anterior pancreaticoduodenal nodes (11 patients). No positive hepatoduodenal and common hepatic artery nodes were found. In univariate analysis, number of positive nodes, and their ratio and location were significantly associated with survival. Only the factor of three or more metastatic nodes had the independent power in predicting a poor outcome in multivariate analysis (P < 0.001). Ampullary adenocarcinoma first spreads to the posterior pancreaticoduodenal nodes and then the anterior nodes. The number of positive lymph nodes, rather than their ratio and location, independently affects survival after curative resection in patients with ampullary carcinoma.