BACKGROUND: The prevalence of obesity and the related factors may be different among different nationalities, and different types of obesity have different influence on cerebrovascular and cardiovascular diseases.OBJECTIVE: To investigate the characteristics and related factors of obesity in Korean and Han populations in rural Yanbian.DESIGN: A randomized controlled observation.SETTING: Antu County Hospital of Jilin Province.PARTICIPANTS: The survey was carried out in 4 towns of Tumen city and Antu county in Yanbian area from August 2004 to August 2005. Totally 1 786 Korean and Han residents above 30 years old were randomly selected, the proportion of nationalities in each area was close. In order to accurately compare the prevalence of obesity among different nationalities, family members of mixed blood were excluded, as well as patients with severe cardiovascular disease and other organic diseases. Informed contents were obtained from all the subjects.METHODS: The information related to this survey was collected by means of home visit and physical examination in the selected community and health center. All the investigators were strictly trained to standardize the contents, procedure and methods before the survey. Related information was collected by means of face-to-face inquisition with uniform questionnaire. ② All the examinees accepted the physical examination in the morning under fasting and resting states by uniform device and examiners. The physical examination included measurements of body height, body mass, waistline,hip circumference, blood pressure. Fasting venous blood (2 mL) was collected to determine serum levels of total cholesterol, triglyceride, high density lipoprotein-cholesterol (HDL-C) and fasting plasma glucose with automatic biochemical analyzer. ③The crude prevalence rate was calculated. The age adjusted prevalence rate was calculated directly by using the sample survey data of Yanbian Korean National Minority Autonomous Prefecture in 2000. ④ The enumeration data were compared with the Chi-square test and u test.MAIN OUTCOME MEASURES: Prevalence and related factors of different types of obesity between different nationalities.RESULTS: ① The age adjusted prevalence was 19.9% and 24.7% in Korean and Han males respectively, whereas 26.3% and 29.7% in females, and it was obviously higher in Han than in Korean population (P ＜ 0.01). The age adjusted prevalence of abdominal obesity, taking waist-to-hip ratio as the diagnostic standard, was 33.9% and 31.6% in Korean and Han males respectively, whereas 53.4% and 51.1% in females, and it was obviously higher in Korean than in Han for both males and females (P ＜ 0.01). The age adjusted prevalence of abdominal obesity, taking waistline/body height ratio as the diagnostic standard, was 48.8% and 44.0% in Korean and Han males respectively, whereas 63.7% and 60.3% in females, and it was obviously higher in Korean than in Han for both males and females (P ＜ 0.01). ② The prevalence of hypertension, hyperglycemia, low HDL-C and metabolic syndrome were markedly higher in Korean than in Han for both males and females (P＜ 0.01); The prevalence of hypertriglycerdemia, smoking and drinking rates were obviously higher in Korean males than in Han ones (P ＜ 0.01); The smoking rate was markedly higher in Han females than in Korean ones (P ＜ 0.01). ③ The occurrences of different types of obesity were associated with hypertension,hyperglycemia, low HDL-C, hypertriglyceridemia and metabolic syndrome in both Korean and Han population.CONCLUSION: ① The different types of obesity and the distribution of influencing factors are different between Korean and Han population in rural Yanbian. ② Different types of obesity are all associated with hypertension, hyperglycemia,low HDL-C, hypertriglyceridemia, metabolic syndrome.