Objective: To observe the effect of pulsed radiofrequency on spinal nerve root for postherpetic neuralgia guided by color ultrasound. Methods: A total of 120 patients in our hospital with postherpetic neuralgia in the innervated areas of cervical nerve, thpracic nerve and lumbar nerve were selected from September 2018 to December 2021. All patients received tramadol and pregabalin but the therapy is not good (VAS above 5.0).They were randomly divided into group A and group B, 60 cases in each group。Group A received pulsed radiofrequency therapy for spinal nerve root guided by color ultrasound; Group B received pulsed radiofrequency therapy for spinal nerve root guided by C-arm, All patients were treated twice, Once a week。VAS, treatment duration, medication use and adverse reactions for the two groups were compared between before and after treatment by 1 day, 1 week, 4 weeks and 12 weeks ,To observe the efficacy and safety of pulsed radiofrequency therapy for spinal nerve root of postherpetic neuralgia guided by color ultrasound. Results: Pulsed radiofrequency therapy of spinal nerve root for postherpetic neuralgia guided by color ultrasound was compared with pulsed radiofrequency therapy for spinal nerve root guided by C-arm. The efficacy was similar, the treatment time was shorter, the medication use was effectively reduced, and the adverse reactions were not increased. Conclusion: Pulsed radiofrequency therapy on spinal nerve root for postherpetic neuralgia guided by color ultrasound is safe and effective, the treatment time is shorter, and the medication use can be reduced effectively.