This thesis discusses the implications of interfaith marriage in Sangalla Selatan District, Tana Toraja Regency in the Perspective of Islamic Law. The problems discussed in this thesis are: 1) the causes of interfaith marriages in South Sangalla District, Tana Toraja Regency, 2) the implications caused by interfaith marriages in South Sangalla District, Tana Toraja Regency, 3) how to minimize interfaith marriages in Sangalla Selatan District, Tana Toraja Regency. This research is a qualitative research that uses normative theological, juridical, sociological, cultural and historical approaches. Data collection techniques was carried out by observation, interviews and documentation. The parties interviewed were religious leaders, community leaders, traditional leaders, heads of the Office of Religious Affairs (KUA), and perpetrators of interfaith marriages in Sangalla Selatan District, Tana Toraja Regency. The results showed that 1) The occurrence of interfaith marriages in Sangalla District, Tana Toraja Regency was caused by several factors, namely: women's freedom to choose a husband, Legitimacy of interfaith marriages by custom, lack of religious knowledge and feelings of liking and love, 2) Implications of marriage different religions, namely: a. it is difficult to realize the purpose of marriage because of differences in spiritual principles so that it has the potential to cause disputes, b. cause problems for children, especially in determining religion and children's schools. 3) Efforts to minimize the occurrence of interfaith marriages can be carried out internally and externally.