The causes of leg length discrepancy in childhood include neurologic, musculoskeletal, tumor and vascular diseases. It may contribute secondary complications such as gait disturbance, scoliosis, hip joint arthritis or cosmetic problem etc. Acquired arteriovenous fistula is a rare cause of leg length discrepancy. Multiple vascular punctures in the neonates, especially in prematures, can result in iatrogenic arteriovenous fistula formation. We report two cases of arteriovenous fistula secondary to vascular punctures, diagnosed by color doppler ultrasonography and CT angiography. The lesions were explored and treated surgically. (J Korean Acad Rehab Med 2010; 34: 607-610)