OBJECTIVE: To investigate the efficacy and safety of ultrasound-guided selective nerve branch blockage in the treatment of lumbar spinal nerve posterior branch syndrome. METHODS: . Ultrasound-guided group used ultrasound-guided selective posteromedial branch and posterolateral branch nerve blockage, and the anatomical positioning group used anatomical localization method to block the posteromedial branch and posterolateral branch of lumbar spinal nerve. Each nerve branch was injected 3 ml of 0.125% ropivacaine. The number of treatment required and prone position time of each treatment were recorded, and the NRS scores of patients at the time points of immediately after the end of the treatment, the first week, the second week, the first month and the third month were evaluated. And adverse events such as local anesthetic allergy and poisoning, local puncture infection, total spinal anesthesia, dizziness, drowsiness, nausea, vomiting and other adverse reactions were observed. RESULTS: <0.05). CONCLUSION: Comparedwith anatomicalpositioning, ultrasound-guided selective nerve branch block for the treatment of posterior branch of the lumbar spinal cord syndrome can reduce the number of treatments and maintain a longer therapeutic effect, but it is also necessary to pay attention to the time of each treatment to avoid dizziness and other adverse reactions.