Abstract: Objective To research the effect of different blood glucose level on the score of minimental state exmination(MM SE) among older people and to provide scientific advice for prevention of cognitive decline in the elderly.Methods Baseline information were collected in 2003 among older people in communities of Guiy ang city and the followup was conducted in 2008.The relation between different blood gluco selevel and score of MMSE was analyzed.Results Single factor analysis showed that sex, age, education level were related to MMSE score.At the base line survey, the MMSE score was 29, 28.5, and 28 for people with normal blood glucose, impaired fasting glucose(IFG) and diabetes mitllitus(DM), respectively, with significant difference among the three groups.In the followup survey, the MMSE score was 27,27, and 26 for people with normal blood glucose, IFG, and DM, respectively, with significant differences among the three groups.There was no significant difference in the decrease of MMSE score among the people with different blood glucose during the follow-up(χ²=2.28, P < 0.05).Multifactor analysis showed that there was a significant correlation bewteen fasting glucose and base line MMSE score and the decrease of MMSE score during the followup.Conclusion A bnormal blood glucose could lead to the decline of cognition in older people.