Vitamin D is a nutrient with emerging roles in cardiovascular, immune, and musculoskeletal function. Vitamin D (VITD) levels are inversely correlated with weight status in adults. This study was designed to determine the prevalence of vitamin D deficiency and insufficiency in a retrospective sample of overweight or obese Soldiers who had attended weight management classes at Fort Bliss, Texas. The study design was a cross-sectional, retrospective review of electronic outpatient medical records of 314 active duty Soldiers. The mean age of the Soldiers was 31, mean body mass index was 32, and 69% were classified as obese. Twenty-one percent of Soldiers were classified VITD-deficient based on having serum 25-hydroxy VITD concentrations < 20 ng/mL, and 51% were classified as insufficient (20-29 ng/mL). In a multivariate logistic regression model, non-Hispanic Black and Hispanic race were significant predictors of both VITD deficiency and insufficiency. The high rate of vitamin D deficiency and insufficiency in this sample of Soldiers is concerning. Given the important roles of VITD in the body, it is imperative that further study of both normal and overweight Soldiers be conducted in order to determine prevalence.