Introduction: The main focus of early intervention is to strengthen the interaction of parents with young children with disabilities, and to ensure that parents become active participants in the development and education of their children. The purpose of this study is to examine the effectiveness of an Early Intervention Program based on Naturalistic Teaching (DÖDEM), which has been developed in order to strengthen the interaction of parents with their children with Down syndrome and to introduce naturalistic teaching strategies to them. Methods: The DÖDEM program was provided face-to-face through group family training sessions and home visits for a group of participants, while it was followed remotely by another group of participants via a tablet computer. The study was conducted with 10 parents and their children with Down syndrome aged 25-48 months. A mixed method research design was used in this study. Results: The findings demonstrate that the parents in both groups made significant progress in interactional behaviours and increased the usage frequency of naturalistic teaching strategies. Furthermore, parents think that the program contributes positively to their interactions with their children and support the development of their children. Conclusion: The results obtained demonstrated that following the DÖDEM program in both ways contributed to significant improvement in the parents' interactional behaviours and the frequency of use of naturalistic teaching strategies. Thus, it can be said that this process has led to a change in both the parents' and children's behaviours.