The prognosis of dermatomyositis is related to the timing of treatment, duration of the disease and the severity of the lesion, most patients are relieved after treatment but are prone to recurrent episodes, some patients with fewer recurrences have a better prognosis, and a small number of patients have serious complications that may threaten their lives. Dermatomyositis is a group of chronic non-suppurative inflammatory diseases of the transverse muscle, characterized by symmetrical weakness of the proximal muscles of the limbs, cervical muscles, pharyngeal muscles, muscle tenderness and elevated serum myosin enzymes, which may involve other organs or tissues such as lungs, heart, joints and blood vessels. Early detection of the disease as well as standardized treatment is conducive to improving the prognosis and reducing muscle skin damage. Most patients show chronic progression with recurrent episodes in the later stages, some patients have a better prognosis with fewer recurrences, and a few may be life-threatening with severe complications. Factors currently thought to influence poor prognosis include advanced age, pulmonary infection, interstitial lung disease, cardiac involvement, malignancy, acute course, dysphagia, fever, and failure to resolve with hormonal therapy alone. After the diagnosis of dermatomyositis is confirmed, it is recommended to follow the standardized treatment prescribed by the doctor, and maintain a healthy lifestyle and optimistic mindset, which can help to improve the prognosis.