Study Objectives Stage I adenocarcinoma of the lung is the most common type of lung cancer. A better understanding of the histopathology and molecular biology of lung cancer might improve the capability to predict the outcome for any individual patient. The purpose of this study was to evaluate several histopathologic and molecular markers in order to assess their prognostic value in stage I adenocarcinoma. Methods Fifty-five patients at the Seoul National University Bundang Hospital were enrolled in the study. Histopathologic factors and molecular markers were selected. Results Multivariate analysis demonstrated that necrosis, lymphatic vessel invasion, E-cadherin, p53, and Ki-67 emerged as independent prognostic factors of recurrence. When patients were grouped according to low or high risk according to the number of factors involved, the difference in disease-free survival between these groups was statistically significant. Conclusions In resected stage I adenocarcinoma, necrosis, lymphatic vessel invasion, E-cadherin, and p53 have been identified as independent predictors of disease-free survival.