Objective To understand the prevalence and distribution features of mild cognitive impairment(MCI)among elderly in Xinjiang Uygur and Han ethnic groups so as to provide evidence for etiological study and prevention. Methods From July 2007 to October 2008, according to the criteria of DSM-IV for MCI,a randomized, stratified and cluster sampling procedure was used in the Uygur and Han elder people aged ≥60 years in south Xinjiang, east Xinjiang and Urumchi region. Results A total of 2986 people were surveyed, including 1519 Uygur people and 1467 Han people, and 1435 males and 1551 females. (1) According to the age composition of national census in 2000, the total crude prevalence rate of MCI was 10.21%, and the total standardized prevalence rate of MCI was 10.58% in Uygur and Han elder people. In general Uygur and Han population, the crude prevalence rates of MCI were 9.61% and 10.84%, and the standardized prevalence rates of MCI were 10.29%and 10.86%, respectively. The prevalence of MCI was higher in Han population than in Uygur population, but there was no statistical difference(χ~2 = 1.225, P>0.05). (2) In males and females, the crude prevalence rates of MCI were 9.34% and 11.03%, and the standardized prevalence rates of MCI were 9.26% and 11.62%, respectively. There was no difference in prevalence rate between different sex populations(χ~2 =2.314,P>0.05). (3) In elder people aged 60～69, 70～79 and≥80 years, the MCI prevalence rates were 6.83%, 13.22% and 22.22% in Uygur population and 8.64%, 12.50% and 19.30% in Han population, respectively, and the prevalence rate of MCI was increased with aging in the two thnic roups(χ_(for trend)~2=34.753, 14.081, both P<0.05). (4)There were statistical differences in prevalence rates of MCI among different education levels, and it was decreased with enhancement of education levels in Uygur and Han population(χ_(for trend) = 14.785, 21.059, both P<0.05). Conclusions In Xinjiang Uygur and Han ethnic elderly people, the prevalence rates of MCI are significantly different among elderly with different ages and education levels, and it is increased with aging, but is decreased with enhancement of education levels.