The specific aims for the study is to evaluate change in Efficacy and safety of shenwu capsule in treating amnestic MCI. Using a randomized controlled parallel group design, 324 older adults diagnosed with amnestic MCI participate in a 6-month supervised protocol of either shenwu capsule or donepezil. Cognitive testing and blood collection will occur at baseline, and months 3 and 6. Before the 6-month intervention, medial temporal atrophy (MTA) or hippocampal volume atrophy on the CT or MRI scan are assessed for all subjects. The results of this study may provide support for a safer and inexpensive treatment strategy that specifically targets individuals with the mild cognitive impairment that directly influence risk of developing dementia for older adults.