OBJECTIVE: To evaluate the method and therapeutic effect of US guided hydrostatic reduction of intussusception in children. METHODS: US was performed in 173 out patient children with suspected intussusception. The 173 cases, diagnosed as intussusception by US (classical US doughnut sign found on US), had US guided hydrostatic reduction. RESULTS: Thirty two cases had difinite US diagnosis of intussusception. The diagnosis was 100% accurate. Of the 32 cases of intusscsception, 30 (93.8%) had successful US guided hydrostatic reduction. Three cases were diagnosed to have ileoileocolic intussusception by US; one of them had successful hydrostatic reduction; and 2 underwent surgery for failed hydrostatic reduction. CONCLUSIONS:US diagnosis of intussusception is reliable and accurate and hydrostatic reduction of childhood intussusception is effective. Though ileoileocolic intussusception can be diagnosed by US, the rate of successful hydrostatic reduction is low.