This research aims to find out how an Islamic education teacher internalises Islamic educational values for children with mild mental disability, what are the Islamic values that can be given to them and what are the supporting factor and obstacles the teacher faces in internalising Islamic educational values for children with mild mental disability. This is a qualitative research. It was conducted in SD-LB Muhammadiyah Gamping. All the necessary informations were provided by various parties, including are the headmaster, Islamic education teacher and the students with mild mental disability at SD-LB Muhammadiyah Gamping. The method of data collection used in this research were observation, interview, and documentation. The data was then presented using descriptive qualitative approach, by analysing using words to gather facts, phenomena, variable and current condition during the research and explain the data which were gathered during the research. The research results are: (1) the Islamic educational values which were internalised for children with mild mental disability in SD-LB Muhammadiyah Gamping has been based on Islamic teachings covering Al-Qur’an, Faith (Aqidah), Morals (Akhlak), and Shari’a. (2) Islamic Education teachers internalise Islamic education values by using role model, habit, advice, monitoring, and punishment/sanction. (3) In the process of internalising Islamic education values, there are some supporting factors and obstacles. The school always conducts religious activities to support the internalisation process of Islamic education values, the school provides relevant books as well as supports from teachers and parents, these are such strong motivations in supporting the internalisation process. As for the obstacles, the school is lack of appropriate facilities and infrastructure, at the same time, the students with mild mental disabilities also have their limitations in internalising the Islamic education values in SD-LB Muhammadiyah Gamping.