objetive: to assess the validity and reliability of a questionnaire for the screening of risk eating behaviors. material and methods: the questionnaire was applied to female high school students in mexico city in october2002, as well as to a sample of eating disorder patients seen at the eating disorders unit of the national institute of psychiatry between september and december 2002. statistical methods included internal consistency analysis (cronbach's alpha) and factor and principal component analysis with oblique rotation. the cutoff point, sensitivity, specificity, and predictive values of the questionnaire were determined using 2 x 2 tables. results: the questionnaire showed a high reliability (·=0.83) and a three-factor structure with 64.7% of the total explained variance. a discriminant analysis showed that almost 90% of cases were correctly classified. conclusions: this questionnaire is reliable and valid for assessing risk eating behaviors in the study population.