The method of cystoscopic transurethral electrodesection of posterior urethral valves and ureteral cysts using a guide wire is described. METHODS: In 21 children with posterior urethral valves and 13 children with ureteral cysts, a guide wire with a 3Fr ureteral catheter was used to perform transurethral electrodesis of the valves or cysts under direct cystoscopic vision. Results: The time used for electrodesiccation was 15-20 min. 21 children with posterior urethral valves showed complete disappearance of the valves and no urethral strictures on postoperative voiding cystourethrography review; 13 children with ureteral cysts showed disappearance of the cysts on postoperative ultrasound. Conclusion Cystoscopic transurethral electrodesiccation using a guide wire is safe, effective, simple, and rapid, and is suitable for the treatment of posterior urethral valves or ureteral cysts in children, especially in neonates and infants.