BACKGROUND The parasacral (PS) approach to sciatic nerve blockade has the potential for safe and effective use in children, but has never been studied in this population. Its potential advantages include increased posterior cutaneous nerve block reliability, potential for hip joint analgesia, and decreased nerve depth, making ultrasound guidance easier. OBJECTIVE To assess the efficacy of an ultrasound-guided PS sciatic nerve block in children. METHODS Nineteen patients, 1-16 years old, scheduled for lower limb surgery with peripheral nerve blockade (PNB) were prospectively enrolled. A PS sciatic block was performed using both ultrasound guidance and nerve stimulation, and 0.5 ml·kg(-1) ropivacaine 0.2% (maximum 20 ml) was administered. Patient demographics, the time to perform the block, the lowest intensity of nerve stimulation, evoked response, identification of gluteal arteries, and amount of narcotic given were recorded. Postoperatively, pain scores, block success or failure, block duration, and complications were recorded. RESULTS The block was performed using the PS approach in 95% of the cases. The success rate was 100% in the PS sciatic blocks performed. The pain scores for all patients in the first postsurgical hour were zero, except one patient that had a pain score of 3 of 10 at 30 min; his pain improved to 0 of 10 after administration of one dose of fentanyl and distraction techniques. The blocks lasted 17.3 ± 5.4 h. No complications were identified. CONCLUSIONS The PS approach is an effective option for sciatic nerve blockade to provide postoperative pain relief in children having lower extremity surgery.