Objective: To examine the association between nutrition knowledge and eating behavior in a predominantly Mexican American population on the Texas-Mexico border. Design: Cross-sectional using data from the baseline survey of the Que Sabrosa Vida community nutrition initiative. Setting: El Paso and surrounding counties in Texas. Participants: Data gathered in 2000 using random-digit dialing telephone survey. Response rate was 42.6% and final sample size was 963. Main Outcome Measures: Knowledge of recommended servings of food items was the independent variable and number of servings of food items consumed was the dependent variable. Data analysis: Multiple logistic regression was used to examine the association between nutrition knowledge and eating behavior. Results: 74% of the population was Mexican American. Nutrition knowledge was a significant predictor of eating behavior for grains (odds ratio [OR] = 6.42; 95% confidence interval [CI]: 2.4, 17.1), dairy (OR = 2.25; 95% CI: 1.5, 3.4), meats (OR = 2.02; 95% CI: 1.5, 2.8), beans (OR = 8.18; 95% CI: 5.1, 13.0), water (OR = 2.49; 95% CI: 1.7, 3.6), but not for fruits and (nonstarchy) vegetables (OR = 1.69; 95% CI: 0.89, 3.2). Conclusions and Implications: Nutrition knowledge predicts eating behavior for all food groups except fruits and vegetables. The role of cultural factors in eating behavior should be investigated to elucidate this finding. Results have implications for developing nutrition education programs for Mexican Americans. (Contains 5 tables.)