Hispanics/Latinos are the fastest growing minority group in the U.S., and represent a diverse variety of ethnic groups with unique heritages. Yet educational and social research often analyzes this group in aggregate. This research, employing 1980 high school senior longitudinal data from the High School and Beyond project, demonstrates substantial differences in post-secondary educational attainment between some Hispanic/Latino groups. Net of a number of individual, socio-economic, family and high school background variables, logit analysis shows that Mexican Americans are significantly below others in post-secondary educational attainment after high school. The results are discussed in regard to future research adopting analysis of individual Hispanic/Latino groups rather than employing the aggregate measure which can substantially misrepresent the relationship between component Latino/a groups and educational attainment.