Our purpose was to investigate acculturation and eating disorders by examining the role of ethnic identity and by utilizing a bidimensional perspective toward two cultures. We predicted that orientation toward European American culture and lower ethnic identity would be positively associated with eating disorders. Participants were 188 Mexican American women recruited from the community (79 with eating disorders and 109 control women). The Structured Clinical Interview for DSM-IV-TR and Eating Disorder Examination were used to establish diagnoses. The Acculturation Rating Scale for Mexican Americans-II and the Multigroup Ethnic Identity Measure assessed Anglo orientation, Mexican orientation, and ethnic identity. Orientation toward Anglo American culture was significantly associated with eating disorders, whereas orientation toward Mexican culture and strength of ethnic identity were not associated with eating disorder status. Findings point to the role of Anglo cultural orientation in the development of eating disorders and underscore the need for future research to utilize bidimensional models.