Islamic Boarding School is an educational institution that fulfills religious values and social intelligence through multicultural education. Currently, Islamic Boarding School pays less attention to the two concepts of religious values and social intelligence. This study aims to explore the implementation of multicultural Islamic boarding schools in Indonesia. The research method is descriptive qualitative. This research was conducted at the Darusy Syahadah Simo Islamic boarding school, Boyolali district, Central Java. This study involved the principal, Islamic religion teacher, head of the curriculum, the learning section, and students. Data obtained using interviews, observation, and documentation. Data sources are classroom implementation, school teaching materials, learning guide books, syllabus, curriculum, and lesson plans. The data were analyzed using a descriptive exploratory model, namely data reduction, data presentation, and interpretation. The results showed that Islamic Boarding schools played an important role in multicultural education. The multicultural values in teaching at Islamic Boarding School include tolerance, togetherness, democracy, solidarity, peace, love, respect, understanding, and apologies. The teaching and learning process must incorporate multicultural values into learning materials, methods, places, and assessments. Teachers must be able to place students as learning subjects in finding methods, locations, and assessments.