Individuals with intellectual disability (ID) need support from direct support professionals (DSPs) to engage in a healthy lifestyle. However, literature shows DSPs feel insufficiently equipped to support a healthy lifestyle. Therefore, the aim of this study is to develop a theory-based program for DSPs to support physical activity and healthy nutrition for people with moderate to profound levels of ID, and to design its evaluation. The Intervention Mapping Protocol (IM) was followed to develop a theory-based program for DSPs. The program evaluation consists of process and feasibility evaluations. This study provided a theory-based program consisting of a training and education section with online and face-to-face components to support DSPs in promoting health for people with ID.