This study explored the prognostic significance and adjuvant chemotherapy benefits in resected patients with stage I non-small cell lung cancer with lymphovascular invasion. A total of 2633 patients who received complete resection with pathologic stage I non-small cell lung cancer in the Shanghai Chest Hospital (2008-2012) were enrolled in the study, of whom 222 were diagnosed with lymphovascular invasion. By using the Kaplan-Meier method and Cox proportional hazard regression model, we explored the impact of lymphovascular invasion on prognosis and determined if the use of adjuvant chemotherapy is associated with improved outcomes in patients with lymphovascular invasion. A propensity score-matched analysis was implemented to reduce the selection bias. Patients with lymphovascular invasion had an unfavorable overall survival and recurrence-free survival in stage I non-small cell lung cancer. Multivariate Cox analysis indicated that lymphovascular invasion was an independent poor prognostic factor for recurrence-free survival (hazard ratio [HR], 2.06; 95% confidence interval [CI], 1.58-2.71; P < .001) and overall survival (HR, 2.04; 95% CI, 1.45-2.87; P < .001) in patients with stage I. After using propensity score-matched pairs, analysis of 65 pairs of patients with lymphovascular invasion indicated a beneficial recurrence-free survival (HR, 0.33; 95% CI, 0.16-0.67; P = .002) and overall survival (HR, 0.30; 95% CI, 0.12-0.74; P = .009) from adjuvant chemotherapy. Lymphovascular invasion was correlated with poor prognosis in patients with stage I non-small cell lung cancer. For such patients, adjuvant chemotherapy was associated with improved survival. Our study suggests that adjuvant chemotherapy might be an appropriate option for patients with stage I non-small cell lung cancer with lymphovascular invasion.