Objective:To explore correlativity of senile dementia of deficiency of kidney essence with polymorphophism of APOE gene. Methods:41 cases of senile dementia and 85 healthy aging persons were divided into 3 TCM syndrome types:syndrome of deficiency of kidney essence

syndrome of orifices confused by phlegm

and syndrome of obstruction of blood stasis in collaterals. DNA in white blood cells was isolated by NaI

and APOE gene was detected by milti-ARMs PCR

and then correlative analysis was made.Results:（1）There was a significant difference between the dementia group and the control group in the gene type ε3/ ε3（P<0.05）

and ε4/ε4 and allelic genes ε3 and ε4（P<0.01）.（2）The relative risk（OR）of ε4 allelic gene with senile demendia attack was 3.92>1.（3）There was significant correlativity between syndrome of deficiency of kidney essence and APOE ε4 allelic gene（P<0.01）.Conclusion:（1）APOE ε4 allelic gene is risk factor and APOE ε3 allelic gene is protective factor for senile dementia.（2）There is close correlation between syndrome of deficiency of kidney essence and APOE ε4 allelic gene.