My study seeks to explore the extent that select secondary and postsecondary indicators predict STEM student enrollment and persistence particularly for Hispanic students. Identifying postsecondary STEM success and college readiness indicators with special focus on malleable indicators that can assist educators, administrators, and policymakers in designing and implementing educational interventions targeted at improving representation of Hispanic students that receive postsecondary STEM degrees. Currently there are few studies that use data from nationally representative samples of students to research the relationship between predictiveness of indicators and postsecondary STEM success, in particular, studies that explore which indicators differentially predict postsecondary STEM outcomes for Hispanic students and Hispanic subgroups. The goals of my research are to determine which indicators are most predictive of future postsecondary success of Hispanic students, and whether these indicators are consistent with previous research on predictors of postsecondary success (Hinojosa, et al., 2016; McClarty & Gartner, 2015). By better understanding the indicators most influential in predicting the future success of Hispanic students, interventions and program decisions can be more effectively tailored to the needs of these students to support increasing representation of Hispanic students enrolling in and persisting in a STEM major or degree. A two-stage analysis plan was implemented for this study. The first stage of analysis involved generating descriptive statistics. The second stage of analysis involved a series of binomial logistic regression models to explore differences between Hispanic students and White students, and within Hispanic group differences moderated by socioeconomic status (SES) and English language learner (ELL) status. The sample for this study was taken from the High School Longitudinal Study of 2009 (HSLS:09) that followed a cohort of students beginning their ninth-grade year of high school. Data were collected on the students in Fall 2009, three years later in spring 2012 of their 11th grade, and as part of second follow-up three years after graduation in 2016.Findings indicate variables from the conceptual framework categories of achievement, behavior, motivation, and social engagement are associated with predicting the likelihood of declaring an NSF supported STEM field of study or degree. The variables of credits earned in science, time spent on math homework/studying and science homework/studying, and participation in math activities were significant for Hispanic students compared to White students, for high SES Hispanic students and for non-ELL Hispanic students, although there was a negative association to the outcome variable for time spent on math homework/studying. Variables from the conceptual framework categories of family circumstances and school characteristics were removed from analysis because of low numbers of responses. However, results from the logistic regression models created explain between 8.9% and 33.6% of the variance in declaring an NSF supported STEM field of study or degree for Hispanic students. The number of jobs in STEM or Science and Engineering (S&E) is expected to increase significantly, and minorities are projected to account for over half of the U.S. population by 2060, with Hispanics being one of the groups to have some of the largest gains. Hispanics, however, along with other minority groups, are underrepresented in STEM or S&E careers and completion of related postsecondary degrees. Further, there is little research using nationally representative data sets that examine "the predictive power of indicators of postsecondary STEM success for Hispanic students" or within Hispanic population differences, including such factors as SES and ELL status (Hinojosa et al., 2016, p.14). Findings from this study can provide educational stakeholders with additional insights aimed at more targeted and earlier interventions and program supports to increase equitable representation of Hispanic students completing postsecondary STEM degrees. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]