Objective: Although diet is a modifiable lifestyle factor to reduce abdominal obesity risk, the relationship between the Health Eating Index (HEI) and waist circumference (WC) has not been studied. The present study aimed to describe relationships between the HEI and abdominal obesity among adults. Design: Secondary data analysis of a cross-sectional national survey, the Third National Health and Nutrition Examination Survey (NHANES III). The HEI data, including the total HEI score and HEI component scores, were collected with a 24 h recall. WC measures were taken during a physical examination. Abdominal obesity was defined as WC $ 102 cm for men and WC $ 88 cm for women. Other covariates were collected during an interview. Subjects: In total 15 658 US adults, men (n 7470) and non-pregnant women (n 8188). Results: The odds of abdominal obesity was 8?3 % (95 % CI 1?8, 14?9 %, P 5 0?014) lower for women and 14?5 % (95 % CI 6?8, 21?9 %, P # 0?001) lower for men with each 10-unit increase in total HEI score (HEI scale, 0-100). For each point increase for the fruit score, abdominal obesity risk decreased by 2?6 % (95 % CI 0?8, 4?4 %, P 5 0?007) for women. Abdominal obesity risk decreased for men with each point increase in saturated fat and variety scores, by 3?1 % (95 % CI 0?1, 6?0 %, P 5 0?042) and 4?0 % (95 % CI 0?1, 7?7 %, P 5 0?043) respectively. Conclusions: Dietary consumption that follows the HEI is associated with a lower risk for abdominal obesity.