The current study investigates the relationship between school connectedness and academic achievement and whether this relationship is moderated by ethnic identity. Participants included 436 Mexican-origin youth attending a middle school in a southwestern U.S. state. Multiple linear regression was used to analyze whether school connectedness is predictive of academic achievement, measured as standardized test scores, and whether ethnic identity moderates the association in this sample of Mexican-origin youth. Findings revealed that after controlling for age, lunch status, generational status, and gender, school connectedness was a positive predictor of standardized test scores in reading and math. Results also indicated that ethnic private regard moderated the association between school connectedness and standardized test scores in reading. These findings underscore the importance of possessing a positive ethnic identity for Mexican-origin youth in predicting academic outcomes.