Paediatric Behçet's disease (BD) accounts for only 2-5% of all patients with BD. Neurological and vascular involvement account for only 3.6% and 1.8% of paediatric BD in China, but both are lethal complications. We report the case of a 12-year-old Chinese boy presenting with recurrent oral ulcers, extensive thrombosis, cerebral sinus vein thrombosis and bilateral inferior pulmonary artery aneurysm. With treatment that included oral prednisone, a monthly pulse of cyclophosphamide followed by mycophenolate mofetil, and anticoagulant therapy, the patient became symptom free, his C-reactive protein and erythrocyte sedimentation rate remained normal, and the right inferior pulmonary artery aneurysm was reduced to normal. However, the left inferior pulmonary artery aneurysm progressively expanded to 64.9 mm×36.2 mm×44 mm. Eventually, the patient underwent left pulmonary aneurysm resection and a left inferior lobectomy. The post-operative maintenance treatment included oral prednisone, mycophenolate mofetil and low-dose aspirin, and the patient was followed for 2 years without recurrence. Additionally, we retrospectively analysed the clinical characteristics of 23 paediatric BD patients from our medical centre and briefly reviewed the literature on paediatric BD.