Introduction: This randomized, double-blind trial aimed to test effect of a Chinese herbal medicine, Qinggongshoutao (QGST) pill, on the cognition and progression of amnestic mild cognitive impairment (aMCI). Methods: Patients with aMCI were randomly assigned to receive QGST, Ginkgo biloba extract, or placebo for 52 weeks. The primary outcome measures were progression to possible or probable Alzheimer's disease (AD) and change in Alzheimer's Disease Assessment Scale-cognitive subscale scores; secondary outcome measures included assessments for cognition and function. Results: Total 350 patients were enrolled, possible or probable AD developed in 10. There were significant differences in the probability of progression to AD in the QGST group (1.15%) compared with placebo group (10%). There was significant difference in Alzheimer's Disease Assessment Scale-cognitive subscale scores in favor of QGST over the placebo group. Secondary outcome measure (Mini-Mental State Examination) also showed benefit in QGST at end point. Discussion: In patients with aMCI, QGST showed lower AD progression rate than placebo at 8.85%, and may have benefit on global cognition. (C) 2019 The Authors. Published by Elsevier Inc. on behalf of the Alzheimer's Association.