This study examines the validity of a Spanish-language dietary behaviors self-report questionnaire (The Latino Dietary Behaviors Questionnaire [LDBQ]) for Latinos with diabetes. The sample (n=252) was Spanish-speaking, female (77%), middle-aged (mean age 55 years), low education (56% <8th grade education), and low income (50% <$10,000 annual household income). Baseline and 12-month measures were collected as part of a randomized clinical trial. LDBQ reliability, validity, and sensitivity to change over time were evaluated using exploratory factor analysis; internal consistency analysis; and correlation analysis using baseline and change scores for LDBQ, 3-day 24-hour dietary recall nutrient mean, and clinical measures. Cronbach's ⍺s were moderate. Four factors were identified at both time points. Significant baseline correlations (r) were found for LDBQ total scores; factor scores; and energy intake (r=−0.29 to −0.34), total dietary fiber (r=0.19), sodium (r=−0.24 to −0.30), percent energy from total fat (r=−0.16), fat subtypes (r=−0.16 to 0.15), and percent energy from protein (r=0.17). Twelve-month data produced a similar pattern. T tests of LDBQ change scores showed significantly greater change in dietary behaviors for the intervention group than for the control group, t(135)=−4.17, P<0.01. LDBQ change scores correlated significantly with mean 24-hour nutrient intake and a subset of clinical measures, but were not associated with clinical change scores (except high-density lipoprotein cholesterol). The LDBQ is a useful tool to assess and target behaviors for change and assess intervention effects.