BACKGROUND AND AIM Single-system ectopic ureter with dysplastic kidney is a rare urologic anomaly. We report our early experience in 4 children who underwent laparoendoscopic single-site (LESS) nephrectomy for single-system ectopic ureters with dysplastic kidney. PATIENTS AND METHODS We diagnosed 4 consecutive children (aged 18-59 months; mean: 3.2 years) with single-system ectopic ureter with dysplastic kidney. A single, experienced surgeon performed LESS nephrectomy using a homemade single-port device in all patients. RESULTS LESS nephrectomy was completed successfully in all 4 patients without complications, insertion of an additional port, or open conversion. Blood loss was minimal. Mean operation time was 83.3 minutes (range: 55-125 minutes), and patients began oral intake on the first postoperative day. Mean postoperative hospital stay was 1.3 days (range: 1-2 days). Urine dribbling and wetting resolved immediately after surgery, and no patient has developed a urinary tract infection to date. CONCLUSIONS LESS nephrectomy for an ectopic ureter with dysplastic kidney is a safe and feasible method with better cosmesis, compared with classic nephrectomy. LESS nephrectomy is a promising method in pediatrics.