Objective To explore medium-term,long-term efficacy of collagenase injected to target site by CT-guided in treatment for lumbar disc herniation. Methods 50 patients with lumbar disc protrusion were treated with CT-guided percutaneous injection of collagenase accurately reaching prominence(target site). Results All patients were followed up 36 to 60 months. The total effective rate was 82.97% (more than 36 months)and82.23%(more than 60 months). Conclusion Grasping indications well, CT-guided percutaneous injection of collagenase target site in treatment of lumbar disc herniation was accurate, safe, simple, effective, and was the preferred treatment for such patients.