This study was aimed to identify the sources for multicultural citizenship character values which became the basis for multicultural citizenship character building. This study also presented a model of multicultural citizenship character building in the curricular program based on the identification of the needs in Madrasah Aliyah in Yogyakarta. The study used the documentation study, a focus group discussion with teachers in the association of civic teachers of Madrasah Aliyah in Yogyakarta, and observations of the implementation of the multicultural citizenship character building in the sample school. There were 30 teachers from 21 schools involved. The instruments uesd were in the form of the lesson plans, observation guidelines, and focus group discussion guidelines. The data were analyzed using the qualitative descriptive analysis. The findings showed the multicultural citizenship character building in Madrasah Aliyah and the efforts to harmonize the Islamic and nationalism identities in Madrasah Aliyah. The integration of the Islamic and nationalism values into the modern Indonesian Islamic education needed to be elaborated further.