Objective:To observe the effect of mild cognitive impairment(MCI)on Treatment by Modified Wuzi Yanzong Granule(MWYG) for 3 months and after drug withdrawal 1 year.Methods: According to the international accepted diagnostic criteria

36 MCI patients were selected and randomly assigned two groups equally

the treated group treated with MWYG(18 cases) and the control group with placebo(18 cases)

with a course of 3 months for both groups and followed up for 1 year. Besides

20 healthy subjects were selected as the normal group.The changes of memory ability and safety before and after treating were observed.Results: Memory quotient(MQ) was significantly lower in MCI patients than in healthy subjects(P<0.01).After treatment it increased in the treated group as compared with that before treatment(P<0.01)

and the inerement was higher the that in the control group(P<0.05).After drug withdrawal 1 year

there was still increase in MQ(P<0.01) than that before treatment in MWYG group

no adverse reaction was found in two groups

and there were two cases of the control group developed into dementia in the elderly.Conclusion: MWYG could improve MCI patients' memory ability and could prevent from MCI into dementia in the elderly.