In recent years, e-learning engagement has attracted much attention because the COVID-19 pandemic has forced schools to shift to online teaching without preparation. Therefore, based on the ecological system theory, this study investigates the relationship between subjective socioeconomic status and e-learning engagement among college students and the mediating effects of perceived social support and self-efficacy. A total of 528 college students in China voluntarily participated in our study. The results showed that perceived social support and self-efficacy independently and jointly mediated the relationship between subjective socioeconomic status and e-learning engagement. The multiple mediation model showed that the high subjective socioeconomic status would increase students’ perceived social support, which could improve their sense of self-efficacy, and further help them put more energy into e-learning. These findings contribute to a better understanding of factors that influence student e-learning engagement.