Background: Accurate prediction of metastatic lymph node is critical to avoid unnecessary gastrectomy and improve quality of life for patients with early gastric cancer. The aim of this study was to develop and validate a nomogram for prediction of lymph node metastasis in early gastric cancer patients. Methods: We reviewed the clinicopathological data of 10595 patients who underwent curative resection for early gastric cancer from 2001 to 2015 at Samsung Medical Center. This model was externally validated by 2100 patients who underwent curative resection for gastric cancer in National Cancer Center. Multivariate analysis using the Cox proportional hazard regression model was performed to develop the nomogram, and discrimination and calibration were evaluated by external validation. Overall survival, disease free survival, and recurrence free survival were compared between gastrectomy groups of 6641 patients and endoscopic dissection group of 999 patients who was performed the treatment in Samsung Medical Center for early gastric cancer by risk on nomogram to demonstrate the efficacy of nomogram. Results: Multivariate analyses revealed that age, tumor size, lymphatic invasion, depth of invasion, and histologic differentiation were significant prognostic factors for lymph node metastasis. The nomogram had good discrimination with a concordance index of 0.845 [95% confidence interval 0.832-0.858], supported by an external validation point of 0.813[95% confidence interval 0.786-0.84]. In low risk on nomogram, endoscopic dissection group had similar overall survival (P = 0.319), disease free survival (P = 0.469) and recurrence free survival (P = 0.091) compared to gastrectomy group. Conclusions: We developed and validated a nomogram predicting lymph node metastasis for early gastric cancer based on a large database. This personalized nomogram is useful to avoid unnecessary gastrectomy after endoscopic dissection resulting in improved quality of life for early gastric cancer patients.