Dermatomyositis, also known as cutaneous heterochromic dermatomyositis, is a non-purulent inflammatory lesion involving the transverse muscle with a predominantly lymphocytic infiltrate, with or without a variety of skin lesions. Dermatomyositis is mostly associated with genetic and viral infections, and the disease is chronic with a long course. Dermatomyositis presents with different symptoms, the initial symptoms are characterized by purple-red edema spots on both upper lids and erythema on the anterior chest, muscle symptoms are characterized by muscle weakness and fatigue in the proximal extremities, and difficulties in lifting and flattening the extremities. Skin symptoms include erythematous rash on the metacarpophalangeal joints, interphalangeal joints, elbows, knees, shoulders, hips, etc. Some patients have keratinized and cracked finger pad skin. Pulmonary symptoms manifest as dyspnea, fever, shortness of breath, severe cough, and susceptibility to lung infections. Cardiac symptoms include heart rhythm disturbances and, in severe cases, myocarditis and heart failure. The diagnosis of dermatomyositis requires routine laboratory tests, urine creatine measurement, myoglobin measurement, autoantibody testing, muscle enzyme profile testing, and histopathological examination. Treatment of dermatomyositis is usually done with oral glucocorticoids, immunosuppressants, and, if necessary, surgery. In addition, a significant percentage of dermatomyositis is associated with malignant tumors, and patients with dermatomyositis need to rule out visceral tumors as well. Patients should maintain a calm state of mind, and also pay attention to warmth, adjust the diet structure, ensure a balanced diet, go out to do a good job of protection, avoid direct ultraviolet radiation, avoid eating seafood, spicy, greasy food, appropriate physical exercise to improve the body’s immunity, to help the recovery of the disease.