Abstract: Objective: To study the clinical characteristics and diagnosis of the interstitial lung disease as the first manifestation of dermatomyositis. Method: a retrospective analysis of 3 patients with interstitial lung disease for the clinical features and treatment of dermatomyositis process first manifestation.Results:3 patients with myalgia, fatigue, difficulty breathing significantly improved, muscle enzymes returned to normal. Conclusion: for respiratory symptoms, joint pain, complement decreased, especially the chest CT interstitial lung disease, should pay attention to check the muscle enzymes, electromyography, muscle biopsy and exclusion of dermatomyositis; clinical diagnosis of dermatomyositis, should be alert to the occurrence of malignant tumor may.