The aim of this study was to review clinical efficacy of acupuncture treatment of mild cognitive impairment. Methods: Randomized controlled trials that performed acupuncture treatment for mild cognitive impairment were retrieved from 6 online databases (PubMed, Cochrane Library, EMBASE, CNKI, NDSL, OASIS) on September 30 th , 2018. Studies were selected according to inclusion and exclusion criteria, and were reviewed by Risk of Bias assessment. Results: In total, 21 studies were included in this review. All studies were Chinese (19 studies published in Chinese and 2 in English). The sample size, 50 to 100, and the number of treatment times, 20 to 30, were the largest range in all studies. The most treatments performed was 30. The longest treatment period was 56 days, which accounted for 33% of the studies. The most frequently used evaluation index was the Mini Mental State Examination followed by the Montreal Cognitive Assessment, each used 17 times and 15 times, respectively. The most frequently used acupoints were GV20, EX-HN1, GB20, and GV24, which accounted for 47% of total number of acupoints used. In 48% of the studies, needle retention time was 30 minutes. Western medicine treatment was the most common control group. Most studies reported that the intervention group was statistically significantly different to the control group. Conclusion: These results suggest that acupuncture for mild cognitive impairment was effective. However, it is difficult to confirm this conclusion because the quality of most of these studies were of low quality.