Objective: To assess the clinical efficacy of single acupoint in the treatment of acute lumbar sprain. Methods: According to the same diagnostic standard, the randomized controlled trial was conducted in several clinical centers. All 320 subjects were digitally randomized into observation group in which Houxi (SI 3) was needled and control group in which Yaotongdian (Ex-UE 7) was needled. The pain severity was scored respectively by the doctors and patients. Results: After 2-course treatment, the short-term effective rates were 89.4% and 82.5% in observation group and control group, and the long-term effective rates were 95.6% and 93.5% respectively. Ridit analysis showed a difference in the short-term effects (P 0.05). Conclusion: Single acupoint is quite effective for acute lumbar sprain, with better effects of Houxi (SI 3) than Yaotongdian (Ex-UE 7).