Danish schools offering "preparatory basic education and training" (FGU schools) have students that are characterized by having different academic, social, or personal problems. In addition, many FGU students are at high risk of suicidal behavior. Many young people with suicide behavior do not seek help and early identification is important for suicide prevention. Teachers are in a position where it could be relevant to implement a gatekeeper intervention. To ensure successful implementation of an intervention, it is important to establish organizational readiness for change, including its innovation-specific capacity, which are the facilitating requirements in the organization specific to the intervention. We aimed to explore the innovation-specific capacity to implement a gatekeeper intervention at FGU schools in Denmark. This study is based on an online survey completed by teaching staff (n = 251) at FGU schools to explore their overall knowledge about and experience with students' suicidal behavior. Limited knowledge of suicide prevention was found among teaching staff. Most knowledge was from personal experience. There is a need for teaching staff to be educated about suicidal behavior. There is a lack of innovation-specific capacity to implement a gatekeeper intervention.