The purpose of this article is to discuss and analyze the phenomenon and process of modernization and westernization in Islamic religious music. Although religious music seems in many societies to change less readily than the secular, many ritual musics of oriental religions gradually change in music concepts, musical structures, and performing contexts for adapting contemporary societies. For examples, Indian Krishina performs her religious music in popular style to attract young men. Buddhism chant in Taiwan is accompanied by electric piano and even performed in the concert hall. Religious music of Indonesian Islam is also influenced by the modernized and westernized society. To have a understanding to the modernization and westernization of Islamic music in Indonesia, the texts will be divided into following parts: combination of Islam and Indonesian traditional music, change of broadcast system of Islamic chant, and popularization of Indonesian Sufi music.