Purpose STING-associated vasculopathy with onset in infancy (SAVI) is a new rare auto-inflammatory disease. The purpose of this study is to report new cases and summarize the manifestations and outcome of SAVI. Methods We made a retrospective analysis of three pediatric patients diagnosed with SAVI between March 2016 and July 2018 in Beijing Children's Hospital. Results Three patients comprised one boy and two girls. The median age of onset was 4 months. All patients had the same de novo heterozygous mutation (c.463G>A, p. V155M) of TMEM173. All patients presented with interstitial lung disease and one coexisted with diffuse alveolar hemorrhage. Rashes were presented in two patients. Other clinical manifestations include febrile attacks, failure to thrive, arthritis, myositis, cerebrovascular involvement, ureteral calculus, gastroesophageal reflux, and malnutrition. Ground-glass opacities were the most common features of chest computed tomography, followed with cysts and reticular opacities. Transbronchial lung biopsy was performed in one patient revealing pulmonary vasculitis. Skin biopsy was performed in one patient with changes of vasculitis. All patients were treated with corticosteroids and two patients received combined treatment of tofacitinib. The therapeutic effects of tofacitinib were limited on interstitial lung disease in both patients and were poor on rashes in one patient. One patient under the treatment of tofacitinib died. Conclusions New clinical aspect of diffuse alveolar hemorrhage is first reported to be associated with SAVI. Unsatisfactory therapeutic effects of tofacitinib are observed in this study and further evaluations are needed.