Abstract: [Objective] To observe the clinical outcomes of modified Smiley Face Rod for treatment of lumbar spondylolysis with spondylolisthesis in adolescents. [Methods] Four adolescent patients suffered lumbar spondylolysis with spondylolisthesis were admitted in our hospital between June 2018 and June 2019. The lesions involved the L4~5 segments in one case, theL5~S1 segments in 3 cases. Before surgery, X-ray film display, all patients were Ⅰ degree Lumbar spondylolisthesis. CT film display the 2 patients were Ⅲ degree lumbar spondylolysis, and 2 patients were Ⅱ degree. MRI film display, the suffered intervertebral disc Pfirrmann classification was type Ⅲ in one case and type Ⅱ in 3 cases. According to ASIA standard for spinal cord injury, all patients were graded as Grade E. VAS score and ODI index were performed before and 3 months after operation. All the patients were treated with modified Smiley Face Rod technology. [Results] All patients were followed up from 0.5 to 1 years with an average of 1 year. The surgical procedure lasted for 85.00±16.83 min with intraoperative blood loss of 237.50±47.87 ml on average. The postoperative drainage volume was recorded as 175.00±64.55 ml. The full weight-bearing achieved at 6.75±5.19 days after operation. There were no incision infections and serious complications in the 4 patients after the operation. All patients achieved complete bony fusion 3.00±0.82 months after operation. The Pfirrmann classification showed that one was changed from type III to type II. The three patients were type II before operation, one patient changed from type II to type Ⅰ and another cases remained unchanged. Both VAS score and ODI index improved significantly. [Conclusion] The operation was the main treatment for lumbar spondylolysis with spondylolisthesis in adolescents. For the adolescent patients with disc damage within Pfirrmann type III and within Ⅰ degree spondylolisthesis, the modified Smiley Face Rod technology treatment had obvious effect. The damaged intervertebral discs were repaired in 3 cases, which can effectively avoid the anterior and middle column fusion surgery.