OBJECTIVE: To test the hypotheses that adolescents have different perceptions of family-environmental factors than do their parents, and that dietary intake of adolescents is more highly associated with the adolescent's own perceptions than those of their parents. DESIGN: Data from self-administered questionnaires were used. PARTICIPANTS: Five-hundred two students aged 12 to 14 years, and one of each student's parents. MAIN OUTCOME MEASURES: Two types of family-environmental factors (ie, family food rules and home availability and accessibility of food) for 3 self-reported dietary behaviors (ie, fruit, snack, and breakfast intake). ANALYSIS: Unpaired t tests, chi-square tests, percentage (gross) disagreement, standardized regression coefficients, and linear regression analyses. RESULTS: For most rules and most perceptions of availability and accessibility, considerable disagreement was found between parents and students. Self-reported intake of fruit and snacks was more highly associated with student measures, but breakfast intake was more highly associated with parent measures of rules and availability. IMPLICATIONS FOR RESEARCH AND PRACTICE: The findings might explain mixed results on the associations between family-environmental factors and children's dietary intake that were found in earlier studies. Researchers need to be aware that in studies into family-environmental determinants of dietary habits using self-reports, the results are possibly influenced by whether the data were reported by parents or by children.