Chronic obstructive pulmonary disease (COPD) increases postoperative morbidity and is associated with diminished long-term survival after lung cancer resection. Whether this is also true for mild-to-moderate COPD is uncertain. We conducted a retrospective analysis of all the patients who underwent lung cancer surgery between 2002 and 2012 in a university-affiliated hospital. The severity of airflow limitation was stratified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) from stage 1 to 4. Data from 1456 cases of lung cancer surgery were reviewed and 1126 patients were included in the study: 672 (59.7%) patients had COPD (GOLD 1, n = 340; GOLD 2, n = 282; GOLD 3, n = 50) and 454 patients had a normal spirometry (controls). Following lung cancer resection, patients with COPD had a higher rate of postoperative morbidities of any kind ( p < 0.0001), in particular, pneumonia (7.0% vs. 3.7%; p = 0.0251) and prolonged air leak (17.0% vs. 8.2%; p < 0.0001) than controls. In-hospital mortality was increased in GOLD 3 COPD but the incidence of other postoperative complications was not influenced by COPD severity. Neither COPD nor its severity influenced long-term survival in this population. To conclude, patients with COPD undergoing lung cancer surgery were at higher risk of postoperative complications than patients with normal respiratory function but the procedure was considered safe. The presence of COPD itself did not influence long-term survival. The results of our study apply mainly to patients with a GOLD 1 and 2 COPD since only a small number of patients with GOLD 3 COPD were involved.