This is a prospective, multi-center, single-arm, target-value clinical trial conducted to evaluate the safety and effectiveness of the Thoracic and Abdominal Endoscopic Surgery System (model WJ-SR01-200) in pediatric surgical procedures. A total of 64 pediatric subjects aged 0 to \<18 years who meet the indications for thoracic and abdominal laparoscopic surgery will be enrolled. The system is used to perform typical pediatric surgeries including pyeloplasty, ureteral reimplantation, ovarian tumor resection, radical resection of Hirschsprung disease, fundoplication, segmental lung resection, and choledochal cyst resection. The primary efficacy endpoint is the rate of non-conversion to open or conventional laparoscopic surgery.The primary safety endpoint is the incidence of device-related or possibly related Clavien-Dindo Grade ≥3 complications from the first incision up to 30 days postoperatively. Secondary assessments include operation time, estimated intraoperative blood loss, pediatric pain scores, transfusion rate, length of hospital stay, device performance, and surgeon intraoperative physical load. Safety is also evaluated by overall complication rate, device deficiency rate, 30-day readmission/reoperation/mortality rates, vital signs, laboratory tests, and adverse events. The trial follows the Declaration of Helsinki and relevant Good Clinical Practice (GCP) guidelines. All subjects will provide written informed consent from legal guardians; assent will be obtained from subjects when appropriate.