Background: Nontuberculous mycobacterial (NTM) lung disease is one of a growing number of chronic health problems that is difficult to cure in aging societies. While it is important to be vigilant about associated comorbidities in order to provide better patient care, data on the prevalence of comorbidities stratified by country or region are scarce. We aimed to elucidate the comorbidities associated with NTM disease based on Japanese health insurance claims data.Methods: Cross-sectional analyses were performed using the claims data for 2014 provided by the Japan Medical Data Center Co., Ltd. Patients aged 20–75 years with ≥3 claims associated with NTM disease were identified and matched to 10 sex-and-age-matched controls that had never made a claim for NTM disease. Thirty-one comorbidities previously suspected to be associated with NTM disease were selected, and the prevalence of these comorbidities compared between cases and controls.Result: Overall, 419 NTM patients (134 males and 285 females) and 4190 non-NTM controls were selected from the JMDC database. Aspergillosis, asthma, bronchiectasis, chronic heart failure, diffuse panbronchiolitis, gastroesophageal reflux, interstitial pneumonia, lung cancer, cancer other than breast, lung, ovary, or prostate cancer, and rheumatic arthritis were associated with NTM disease in both males and females. Chronic obstructive pulmonary disease was associated with NTM in males while chronic kidney disease, osteoporosis, and Sjögren syndrome were associated with NTM in females.Conclusion: NTM disease was associated with multiple comorbidities that should be considered when providing medical care to individuals with NTM disease.