Since the fall of the Soeharto regime in 1998, socio-political conditions for ethnic Chinese in Indonesia have drastically improved, while the governmental supervision of religious institutions has been weakening. This article focuses on the relatively inconspicuous yet significant on-going changes regarding 'Chinese Religion (Agama Tionghoa)’ in Post-Soeharto Indonesia. In the early 20th century, Peranakan Chinese (ethnic Chinese who had become localized both in a cultural sense and in terms of descent) intellectuals in the Dutch East Indies discovered Confucianism and developed 'Three-teaching (Sam Kauw)’ in their effort to seek for 'a spiritual pillar for Chinese'. This move was stimulated by the Chinese nationalist movement, and the Christianization of ethnic Chinese. 'Three-teaching', or 'Tridharma’ in Indonesian, was conceptualized as a holistic 'Chinese traditional religion' encompassing Buddhism, Confucianism and Taoism as well as ancestral worship and folk religious practices in Chinese temples. From the mid-1960s under the Soeharto regime, however, the organizations holding up Tridharma functioned merely as protectors of Chinese temples, and carried out few 'religious activities'. In the Post-Soeharto era, following the changes in the landscape of 'Chinese Religion' caused by, among others, the re-acknowledgement of Confucianism as an officially recognized religion, the Tridharma organizations have started reasserting their raison d’etre by establishing doctrines and standardizing ritual. In this article, I offer an overview of these historical processes, before reviewing the recent substantial attempts of religious systematization made by three Tridharma organizations; one in West Java (Majelis Agama Buddha Tridharma Indonesia), one in East Java (Perhimpunan Tempat Ibadat Tri Dharma se- Indonesia), and the latter’s branch in Central Java. Further, I analyze the sources of religious knowledge drawn on to support these systematizing efforts.