Background: We performed a six-week study of pramipexole vs. a placebo in Chinese restless legs syndrome patients. Methods: Overall, 305 enrolled patients were assigned randomly in a 2:1 ratio to the pramipexole group (N = 202) and the placebo group (N = 103). Results: Of 287 patients in the full analysis set, the pramipexole group showed significant improvement compared with the placebo group in the change of their International Restless Legs Syndrome Study Group Rating Scale of Severity (IRLS) total score from baseline to week 6 after adjustment of centers and baseline characters (-15.87 +/- 0.66 vs. -11.35 +/- 0.92, p < 0.0001) and in the proportion of patients who were "much improved" and "very much improved" when measured by Clinical Global Impressions-Improvement (81.9% vs. 54.3%, p < 0.0001). At week 6, the IRLS responder rate was 73.8% (pramipexole) and 48.9% (placebo) (p < 0.0001) and the patient global impression responder rate was 68.6% (pramipexole) and 43.5% (placebo) (p < 0.0001). The proportion of adverse events was 62.9% in the pramipexole group and 43.7% in the placebo group, respectively. No deaths occurred. Conclusion: Pramipexole was effective and well-tolerated in Chinese patients with restless legs syndrome. (C) 2011 Elsevier B.V. All rights reserved.