Existing inequalities in STEM-related vocational-technical education (VTE) programs are more prevalent than within 4-year programs. Situated in Chile, this study tests whether Social Cognitive Career Theory (SCCT) adequately explains career development among students enrolled in STEM-VTE programs. In doing so, it also examines how external factors such as supports, barriers, and secondary track differentially affect career development by gender. Using a sample of 698 students in their second year of STEM-VTE studies, we confirmed that the SCCT model produced a good fit for the data in this alternative institutional setting. The findings also showed few gender differences in the effects of external factors on self-efficacy and career expectations, except for teaching support that substantially alters these cognitive factors to more extent among males than females. Moreover, although self-efficacy beliefs were similar between gender, gains in career expectations due to these beliefs are lower for female students. We conclude by discussing implications for future research and practice.