Continuous intravenous epoprostenol was the first treatment approved for pulmonary arterial hypertension (PAH) but administration through a central venous line carries risks of thrombosis and sepsis, particularly in children. We sought to evaluate the safety, efficacy and management of subcutaneous (SC) treprostinil in children with PAH. Fifty-six children (median age 65, range 1-200 months) were treated with SC treprostinil. Clinical status, echocardiography, NT-proBNP, and site pain and infection were evaluated. Right heart catheterization was performed in 54 patients before starting SC treprostinil infusion and was repeated at 6 months in 31 patients. Treatment was well tolerated in 79% of patients. Site pain resistant to simple analgesics occurred in 12 patients (21%), but could be managed in 9/12 children. At 6 months, 3 patients had died, 4 had received a Potts shunt and 1 underwent lung transplantation. Among the 48 treated patients, 40 (83%) showed significant improvement in WHO functional class, 6 minute walk distance, NT-proBNP and pulmonary vascular resistance (p < 0.01 for all parameters). At last follow-up (median 37 months), ten patients had died, 2 underwent a lung transplantation and 8 underwent a Potts shunt. In 30 of the 36 remaining treated patients, improvement of clinical status was sustained. No children developed sepsis and 12 had minor site infections. Subcutaneous treprostinil infusion is an effective therapy without serious side effects in children with PAH. Site pain can be managed with simple analgesics in most children.