PURPOSE: To evaluate the surgical outcomes of lung cancer patients with idiopathic interstitial pneumonia (IIP) and/or coronary artery disease (CAD). METHODS: The subjects of this retrospective study were 2830 patients who underwent surgical resection for lung cancer between 2009 and 2018. Seventy-one patients (2.6%) had both IIP and CAD (FC group). The remaining patients were divided into those with IIP only (group F), those with CAD only (group C), and those without IIP or CAD (group N). We compared mortality and overall survival (OS) among the groups. RESULTS: The 90-day mortality and OS were poorer in group FC than in groups C and N, but equivalent to those in group F. Multivariate analyses revealed that IIP (odds ratio [OR] 3.163; p = 0.001) and emphysema (2.588; p = 0.009) were predictors of 90-day mortality. IIP (OR 2.991, p < 0.001), diabetes (OR 1.241, p = 0.043), and a history of other cancers (OR 1.347, p = 0.011) were all predictors of OS. CONCLUSIONS: Short-term and long-term mortality after lung cancer surgery were not dependent on coexistent CAD but were related to IIP. Thus, computed tomography (CT) should be done preoperatively to check for IIP, which is a risk factor for surgical mortality.