Type 2 diabetes is the main type of diabetes in diabetic population. Along with the rapid changes of life style and increased life expectancy, the prevalence of type 2 diabetes increases rapidly worldwide. However, strong evidences have shown that genetic factors play important roles in the pathogenesis of type 2 diabetes, except for some rare subtypes of type 2 diabetes. The genetic patterns of the common forms of type 2 diabetes do not follow the role of classic Mendelian inheritance. Therefore, the type 2 diabetes is regarded as a complex disease caused by interaction between gene and environment. However, little progress has been made during past two decades in the genetic epidemiology of type 2 diabetes. This article reviews the current status of genetic epidemiology of type 2 diabetes and proposes strategies for future researches.