A limited body of research has explored the self-care practices of school psychology trainees (graduate students). Therefore, the current study undertook a comprehensive approach towards examining the relationship between professional self-care practices and perceived stress, academic performance, affect, and psychological well-being amongst school psychology graduate students across Canada. Specifically, this study assessed the predictive nature of professional self-care practices on the outcome variables (academic performance, psychological well-being, and affect) and investigated if self-care influenced the relationship between perceived stress and psychological well-being. Participants included 102 Canadian school psychology graduate students (female: 94, male: 8, M age: 26.9). Results indicated that professional support and life balance self-care practices predicted increased psychological well-being and that life balance predicted positive affect. Additionally, the results indicated that professional self-care practices strengthened the inverse relationship between perceived stress and psychological well-being, suggesting that self-care practices can buffer the negative effects of perceived stress on well-being. These results highlight the important role that professional self-care plays for school psychology trainees and may guide researchers and practitioners on ways to improve self-care intervention practices within professional and training settings.