OBJECTIVE: To identify schoolchildren"s dietary patterns and investigate the demographic, social, and economic determinants of the differences found between patterns. METHODS: The sample consisted of 1,330 students aged 11 to 17 years attending the public schools of Salvador, Bahia, Brazil. The subjects' food intake data were collected by a semiquantitative Food Frequency Questionnaire comprising 97 food items. All information was collected during a single interview. The exposure variables were gender, age, and socioeconomic class, and the outcome variables were categorized food consumption pattern in "mixed pattern", "traditional pattern", and "healthy pattern". The data were treated by simple and multiple linear regression analyses and the dietary patterns determined by factor analysis. RESULTS: Most participants were female (56.9%) and over 13 years old (79.2%). The "mixed pattern" was positively associated with females (β=0.181, p<0.001). The "traditional pattern" was negatively associated with classes D, C, and B (β=-0.149, p<0.007), and the "healthy pattern" was negatively associated with females (β=-0.200, p>0.0001) and classes D, C, and B (β=-0.125, p<0.023). CONCLUSION: Three dietary patterns were identified among the adolescents, namely mixed, traditional, and healthy. Gender and socioeconomic class were associated with dietary patterns. Male teenagers and those in the lower socioeconomic classes had a healthier dietary pattern than their peers of higher socioeconomic classes and females.