Background. Little is known regarding the relationship between overall diet quality and physical performance among older adults. We examined the association between overall diet quality, as measured by the US Department of Agriculture's Healthy Eating Index-2005 (HEI-2005), and physical performance, as measured by gait speed (n = 2,132) and knee extensor power (n = 1,392), among adults aged 60 years or older. Methods. Using data from the 1999-2002 National Health and Nutrition Examination Survey, multiple linear regression models controlling for age, gender, race/ethnicity, education, smoking status, comorbidities, medication use, cognitive function, body mass index, and physical activity were used in the analyses. Results. After adjusting for age, gender, race/ethnicity, education, and smoking status, total HEI-2005 scores were positively associated with both gait speed (p for trend =. 02) and knee extensor power (p for trend =. 05). Older adults with higher HEI-2005 scores had a faster gait speed (p =. 03 for both Quartile 3 and Quartile 4 vs quartile 1) compared with those with HEI-2005 scores in the lowest quartile. Those with HEI-2005 scores in Quartile 4 had a greater knee extensor power compared with those with HEI-2005 scores in the lowest quartile (p =. 04). The associations between HEI-2005 scores and physical performance remained after further adjustment for comorbidities, medication use, cognitive function, and body mass index. However, the associations were no longer statistically significant after further adjustment for physical activity. Conclusion. Adherence to overall dietary recommendations is associated with better physical performance among older adults. © 2011 The Author.