Clinical characterization of pre-diabetes is indispensable to set up proper national diabetes prevention strategies. Although it has been predicted that Korea will have the highest prevalence of diabetes among OECD countries by the year 2030, there have only been a few studies on this issue. The Korean Diabetes Association analyzed normal fasting glucose (NFG) and impaired fasting glucose (IFG) population according to FPG level, as follows: NFG (fasting plasma glucose [FPG] < 100 mg/dL), stage 1 IFG (100-109 mg/dL) and stage 2 IFG (110-125 mg/dL) in a pooled analysis of four community-based cohort studies in Korea. And the data showed that IFG2 was more poor metabolic profile compared to IFG1. With these results, clinical practice guidelines for type 2 diabetes in Korean Diabetes Association recommend different screening methods according to IFG stage. In this presentation, I will show you some results of analyses for clinical characteristics IFG1 vs. IFG2 using data of Korea National Health and Nutrition Examination Surveys (KNHANES). KNHANES 2005 showed that degree of obesity increased with an increase of FPG in range of NFG, peaked in IFG1, and then plateaued in IFG2 and diabetes. KNHANES 2011 showed that the prevalence of microalbuminuria began to increase in IFG2. KNHANES 2007-2009 showed that IFG2 and diabetes were independently associated with decreased forced vital capacity (FVC) and suggest that the FVC may begin to decrease in IFG2. These results suggest that the association between pre-diabetes and some diabetes complications and clinical characteristics of IFG2 may be different to those of IFG1. Large prospective studies of the association between pre-diabetes and diabetes complications/cardiovascular outcomes, as well as re-analyses of the datasets of previous cohort studies, are required.