Objective: Although upward transfer in science, technology, engineering, and mathematics (STEM) fields represents a prominent national policy concern, community college students' aspirations for transfer in STEM are often impeded, resulting in lower transfer rates. This study investigated four aspects of community college STEM students' aspirational experiences and behaviors with regard to transfer: support for transfer, transfer service usage, transfer-oriented interactions, and transfer information acquisition. Particular attention was paid to how these factors may impact students' aspirational momentum differently based on gender and race/ethnicity. Method: The study drew upon survey and administrative records from 1,245 first-time students beginning in STEM majors or courses at three large comprehensive 2-year institutions in a Midwestern state. A logistic regression model with interaction terms was employed to explore whether and how the relationship between students' aspirational momentum toward STEM transfer and their aspirational experiences and behaviors vary across gender and race/ethnicity. Results: Results indicate that, overall, students engaging in more frequent transfer service usage were significantly more likely to have aspirational momentum, but this relationship is weaker among female students, compared with males. Also, Black and Hispanic students' aspirational momentum was significantly less affected by support for transfer than for White students. In contrast, the effect of transfer service usage on aspirational momentum for Black students was significantly stronger than for White students. Contributions: Our findings hold implications for how to cultivate aspirational momentum toward transfer in STEM, especially how to resolve potential gender and racial disparities within this unique and pivotal transfer pathway.