The incidence of postoperative pulmonary torsion is not frequent but it has a high mortality rate once it occurs, and prompt diagnosis and treatment are required. From past reports, it is considered effective to point out disruption of pulmonary blood flow by contrast-enhanced computed tomography (CT) examination for diagnosis. However, the comparison of pre- and post-operative plain CT images is considered to be useful in diagnosing lung torsion, and postoperative CT lung window setting sagittal images were examined in three cases of postoperative lung torsion. Results indicate that pulmonary torsion of the middle lobe after right lower lobectomy and the middle lobe after right upper lobectomy can be diagnosed by the present method.