Objective:To study on symptom characteristics and TCM syndrome types of mild congnitive impairment（MCI）

and reveal the relation of TCM syndrome types of MCI with metabolism of free radicals and cholin esterase.Methods:With reference to internationally acknowledged criteria for MCI diagnosis at present

44 cases of MCI were selected and 20 healthy persons were used as controls.Relative neuropsychological scales tests were conducted and TCM syndrome types were established.Serum acetycholin esterase（AchE）

superoxide dismulase（SOD）activities

serum malondialdehyde（MDA）content and DNA defect rate in mitochondria of white cells were determined.Results:27 cases（61.4%）of deficiency syndrome

17 cases（38.6%）of coexistence of deficiency and excess syndromes and 93.18% patients of MCI had the symptoms of kidney-deficiency and hollow marrow.Serum MDA level and AchE activity and the DNA defect rate of mitochondria in white blood cells in the patients of deficiency syndrome and coexistence of deficiency syndrome and excess syndrome increased significantly and SOD activity and memory quotient significantly decreased as compared with the healthy persons.Memory quotient

serum MDA level and AchE activity in the patients of coexistence of excess and deficiency syndromes increased significantly and SOD activity decreased significantly as compared with the patients of deficiency syndrome.Conclusion:TCM syndrome types of the patient of MCI have objective substance basis

i

e.varying degrees of memory impairment and disturbances of metabolism of free radicals and AchE.