Abstract: Objective: To evaluate high-resolution computed tomography (HRCT) features of dermatomyositis-/polymyositis- associated interstitial lung disease (DM/PM-ILD). Methods: We retrospectively reviewed the HRCT images of 148 patients with DM/PM-ILD at the First Affiliated Hospital of Xi’an Jiaotong University between Jan. 1, 2014, and Dec. 31, 2019. Results: The HRCT features of DM/PM-ILD were characterized by ground-glass opacities (GGO) (87.2%, 123/141), interlobular septal thickening (78.0%, 110/141), intralobular interstitial thickening (63.8%, 90/141), consolidation (29.1%, 41/141), subpleural lines (26.2%, 37/141), traction bronchiectasis (19.9%, 28/141), and honeycombing (3.5%, 5/141). Pneumomediastinum (3), pleural effusion (15), and pericardial effusion (18) were also observed. The two main radiological patterns were non-specific interstitial pneumonia (NSIP) and organism pneumonia (OP). Conclusion: HRCT features of DM/PM-ILD are heterogeneous, with various radiological patterns. Mastering the main characteristics of HRCT manifestation and the radiological patterns of DM/PM-ILD will be helpful for early identification and timely treatment.