Objective To investigate the natural outcome and influencing factors of glucose tolerance reduction (IGT) in the developed rural urbanization area.Methods A 15-yr outcome tracking survey on 126 cases of IGT population confirmed by epidemiol. investigation in 2000 in Shajing Street of Shenzhen City was carried out.A unified survey form was adopted to investigate medical history, measure height, weight, waist circumference and blood pressure and calculate body mass index (BMI).Standard oral glucose tolerant test (OGTT) was used to measure fasting plasma glucose (FPG) and 2h postprandial plasma glucose (2hPG).Diabetes mellitus (DM) and glucose tolerance (IGT) were diagnosed according to the 1999 WHO diagnostic criteria.Obesity was diagnosed according to Chinese adult overweight and obesity prevention and control guidelines.Risk factors were analyzed by Logistic stepwise regression.Results Sixty-five cases converted to DM among 126 patients with IGT, the conversion rate was 51.6%, and the annual conversion rate was 3.44%.Compared with the patients converted to normal glucose tolerance (NGT group), age, BMI, FBG and 2hPG were significantly higher in DM group, and the differences were statistically significant (P < 0.05).Logistic stepwise regression anal. results showed that age (OR = 1.166, 95%CI 1.054-1.311, P = 0.0031), body mass index (BMI) (OR = 1.445, 95%CI 1.152-2.802, P = 0.0210) and 2hPG (OR = 3.015, 95%CI 1.166-7.709, P = 0.0214) were the risk factors of IGT converted to DM.Conclusion The main influencing factors of IGT converted to DM are age, obesity and 2hPG.Low conversion rate is related to low incidence of IGT and obesity in local.Lifestyle intervention is the most effective means of prevention, should strengthen the publicity and education of DM, maintain good cooking mode, strong motion, control overweight and obesity, in order to reduce the incidence of DM, which has a certain guidance meaning for DM prevention in economically developed rural urbanization area.