Key message Diffuse pulmonary meningotheliomatosis (DPM) is an ultra‐rare pulmonary disease characterized by innumerable bilateral minute meningothelial‐like nodules, sometimes presenting a characteristic ‘cheerio‐sign’ on imaging. Most patients with DPM are asymptomatic and experience no disease progression. Although little is known about its nature, DPM may be associated with pulmonary malignancies, mostly lung adenocarcinoma.