Engaging aspiring pre-service teachers (PsTs) is crucial for achieving sustainable waste separation and recycling levels within the academic community. In this study, we considered three supplementary factors from the Theory of Planned Behavior (TPB) to elucidate the formation of actions related to engaging in waste separation and recycling intention on campus (WSRIs). An online survey, utilizing a questionnaire, was administered to over 530 PsTs in East Java, Indonesia, comprising 380 females and 152 males. Structural equation modeling was employed to analyze the main factors and paths influencing WSRIs. The waste separation and recycling intention of PsTs were primarily influenced by five internal subjective factors and three external factors. Among these, environmental education (EE), perceived behavioral control, and environmental knowledge (EK) displayed the most significant associations, with EE having the greatest direct effect. Conversely, attitude had minimal effect on WSRIs. Moreover, to improve waste separation and recycling practices on campus, it is recommended to integrate EK into daily life, emphasizing its importance in achieving these sustainable goals. [ABSTRACT FROM AUTHOR]