The purpose of this study wasto examine college students’ enrollment decision in STEM majors with a focus on students’ family SES. This study examinedwhether there is systematic association between students’ family SES and their enrollment in STEM majorsand if so, what the direction and magnitude of the association is. The overarching research question that guided this study was: Do the enrollment in STEM majors vary for students with different family SES background? Specifically, this study addressedthe following research questions: (1) Is students’ family SES related to their decision of whether to enroll in a STEM major in college? (2) Does the enrollment decision in STEM fields vary for students with different college investment levels? and (3) Does the enrollment decision in STEM fields vary at institutions with different scales and levels of STEM major offerings?