This study explored the role of occupational therapy practitioners (OTPs) in school-based practice addressing mental health (MH) needs of all students. A sequential explanatory mixed method design which included two stages. Stage One: 61 OTPs in Southern California completed an online survey. Stage Two: 15 OTPs engaged in either an interview or a focus group. The survey data revealed that OTPs spent less time addressing MH issues than their caseload seemed to require. Autism spectrum disorder and anxiety disorder were addressed more frequently in comparison to grieving, thought disorder, schizophrenia, bipolar disorder, and self-harm. Respondents were more likely to address MH issues using individual intervention and prevention strategies rather than a promotional approach. The majority of respondents were unfamiliar with the American Occupational Therapy Association School MH Tool Kit. Four themes emerged from qualitative data: "Process of receiving support and services," "OTPs perceived scope of practice in school-based settings," "Approaches to address MH," and "Barriers to address MH needs in school-based practice." Currently OTPs in Southern California face a number of challenges in addressing MH problems among children in school-based settings.