The present study aimed to evaluate the incidence of type 2 diabetes mellitus (T2DM) and associated risk factors among adults in a rural community of Thailand. A prospective cohort study was conducted in a rural community of Thailand. Among 1358 nondiabetics ≥18 years, fasting plasma glucose (FPG) was measured at baseline in 2008 to 2010 and at follow-up evaluation in 2015. After follow-up of 5213 person-years, 122 new cases of T2DM were ascertained corresponding to cumulative incidence of 23.40 per 1000 person-years. The independent factors associated with T2DM were age, male, prehypertension, hypertension, waist circumference, and impaired FPG. The incidence of T2DM in Thailand is high, and many risk factors are converging. The focus of public health efforts should be on abdominal obesity, hypertension, and impaired FPG. Special attention in terms of preventive strategies must be paid to individuals with impaired FPG, as this state is the most prominent predictor of developing T2DM. Keywords incidence of type 2 diabetes mellitus, risk factors of type 2 diabetes mellitus, prospective cohort study, rural community, Thailand