Background: Teachers are important gatekeepers in suicide prevention for children and youth, yet little is known about factors that contribute to suicide prevention training effectiveness and the influence of student suicidality on teachers' role as gatekeepers. Objective: This study examined teachers' attitudes and self-efficacy in suicide prevention including an examination of suicide prevention training and exposure to student suicidality. Researchers examined incremental prediction of the relationship between teachers' self-efficacy, outcome expectations, and outcome values following prevention training. Methods: Participants included teachers in PreK-12th grade schools in the United States (N = 505). Researchers used non-parametric statistics to examine group level differences and a structural equation model (SEM) to test the proposed theoretical model. Results: Teachers who experienced a student death by suicide reported significantly higher levels of gatekeeper reluctance than teachers who had not experienced a student death by suicide (p < 0.01). Similarly, teachers who encountered students with suicidal thoughts reported greater levels of gatekeeper reluctance (p < 0.01) and higher self-efficacy to engage in suicide prevention (p < 0.05) compared to teachers who had not had this exposure. Results of the SEM indicated an adequate goodness of fit and fit statistics [X[superscript 2] (87) = 194.420, p = 0.000; CFI = 0.95; RMSEA = 0.05]. The model remained in-tact when exposure to student suicide was added. Conclusions: Findings support the importance of supporting teachers continued engagement in youth suicide prevention and prevention training that targets specific outcomes in teachers' attitudes and efficacy.