The purpose of this study was to compare the body mass index (BMI) and dietary intakes of Chamorro (n= 66) and Filipino (n= 61) adults, ages 25–65 years, living in Guam. Participants were recruited via community-based sampling; however, recruitment was targeted to ensure approximately equal numbers from each ethnic group, equal numbers of men and women within each ethnic group, and proportional representation of the main geographic areas of the island. In addition, subjects were recruited and stratified based on the 2000 Guam Census Data to assure proportional distribution by age. Dietary energy density (ED) was calculated as kcal/g and compared by gender, ethnicity, and obesity status. Mean BMI for Chamorros was significantly higher than for Filipinos, and a significantly higher proportion of Chamorros (49%) were obese compared to Filipinos (20%). Chamorros reported higher ED than Filipinos (1.9 kcal/g versus 1.6 kcal/g), although the difference was significant among males only. Non-obese subjects had a lower ED than obese subjects (1.9 versus 2.3 kcal/g). Overweight and obese subjects both reported a significantly higher% energy consumed as sugar-sweetened beverages than healthy weight subjects (8% and 9% versus 3%). Differences in ED may contribute to differences in obesity rates between Chamorros and Filipinos in Guam, particularly among men, and lowering ED may be an appropriate goal for nutrition interventions.