In this study, we focused on teachers’ knowledge and awareness of LGBT+ issues in a Catholic secondary school in Ireland. We explored the barriers teachers encounter that prevent them from being openly supportive of LGBT+ students. For this study, 40 teachers completed an online questionnaire, which was followed by a smaller focus group interview comprising 6 teachers. The findings demonstrate a lack of knowledge about LGBT+ issues among teachers, and the majority have not received any training related to this topic. This can be linked with their lack of awareness of policies, supports, and resources available to help LGBT+ students. The findings suggest a lack of self-awareness because some teachers were not supportive of issues that affect LGBT+ students but believed otherwise. It also is clear from the results that there are mixed perceptions of what is acceptable to discuss and support due to the Catholic ethos of the school. These findings reflect several barriers to supporting LGBT+ students and issues.