Objective  To analyze the changes of serum biochemical indexes with age and gender in Xinjiang Uygur and Kazak populations, and to compare the differences of serum biochemical indexes between Xinjiang Uygur and Kazak populations in gender and age.   Methods  Totally 511 Xinjiang Uygur and Kazak healthy adults were randomly selected from a hospital in Xinjiang Uygur autonomous region for normal physical examination, including 252 and 259 Xinjiang Uygur and Kazak healthy adults. Serum biochemical indexes were detected by CX-7 automatic biochemical analyzer produced by Beckman, USA, and statistical analysis was conducted by variance analysis, t test, correlation analysis and chi-square test.   Results  Xinjiang Uygur nationality and Kazak serum biochemical indexes for the male and the female, including glutamic-pyruvic transaminase(GPT), direct bilirubin (DBil), uric acid(UA), creatinine(Cre) and urea(Ure), glucose (Glu), total bilirubin（TBil）, cystatin C(Cys-C) increased with the growth of the age, and sex between different age groups were statistically significant (P<0.05), the men than women with age (P<0.05); High-density lipoprotein (HDL) decreased gradually with age, and low-density lipoprotein (LDL), triglyceride and total cholesterol increased gradually with age, with statistical differences among different age groups (P<0.05). Triglycerides(TG), total cholesterol (TC) and LDL were lower in females than in males in all age groups before the age of 50, and HDL was higher in females than in males (P<0.05), and there was no difference after the age of 50 (P>0.05). There were statistically significant differences in Glu, TG, TC, LDL and HDL between Xinjiang Uygur and Kazak people of the same  ender and age group (P<0.05).   Conclusion  The serum biochemical indexes of Uygur and Kazak in Xinjiang are different in different ages and genders. The Glu and lipid levels of Uygur nationality in Xinjiang are different from those of Kazak nationality.