Background: Diabetes is the seventh leading cause of death in the United States. More and more people have suffered from diabetes and its serious complications including heart disease, blindness, etc. The U.S. Department of Veterans Affairs (VA) reported that nearly 25% of veterans, enrolled in the Veterans Health Administration (VHA),have diabetes, which is much higher than the general population. Objective: This study aimed to estimate the prevalence of diabetes in the U.S. veterans using the up-to-date National Health and Nutrition Examination Survey (NHANES) data since VHA has a relatively low coverage (less than 30% of veterans each year were enrolled). Methods: Five biennial cross sectional surveys (NHANES) from 2005-2014 were used in this study. Total 2,940 veterans were included to estimate the prevalence of diabetes. Total diabetes was defined as any participant who had at least one of four conditions: (1) a hemoglobin A1c at least 6.5%, (2) fasting plasma glucose (FPG) at least 126mg/dL, (3)a 2-hour plasma glucose (PG) at least 200mg/dL, (4) diagnosed with diabetes by a doctor or other health professional. Results: The overall prevalence of total diabetes(including diagnosed and undiagnosed diabetes), undiagnosed diabetes and obesity were 20.54%, 3.37% and 40.68%, respectively. The family poverty level and education were significantly associated with the presence of diabetes with p=0.005 and 0.03,respectively. Highest prevalence diabetes and obesity existed in veterans aged 65yrs and over and 45-64yrs, respectively. The overall prevalence trend of diabetes significantly increased from 15.52% (95%CI: 12.36-18.68%) in 2005-2006 to 20.54% (95%CI:15.92-25.17%) (p=0.04 for trend test) and prevalence significantly increased in male veterans (p=0.04) and those who did not finish high school education (p=0.04) and who had college education (p=0.03). Conclusion: In 2013-2014, the estimated prevalence of diabetes was 20.54% among U.S. veterans, with higher prevalence among participants who were 65 years old or older, and had low socioeconomic status (including less education and poverty status).