This study examines the intricate relationship between language ideology, Taiwanese identity, and the adoption of the romanized Taiwanese system (Pe?h-oe-ji) within the Taiwanese language (Tâigí) speaking community, against the predominance of Mandarin. It explores the multifaceted motivations of Tâigí users for preferring Pe?h-oe-ji, including affirming ethnic and national identities, enhancing linguistic proficiency, and revitalizing Tâigí. Through interviews with 27 Pe?h-oe-ji Tâigí writers, this research elucidates their literacy practices that aim to challenge Mandarin-centric discourses and the enduring impacts of Chinese colonization. These efforts demonstrate a commitment to decolonization and the revitalization of Tâigí to bolster Taiwanese ethnocultural and national identities. The findings illuminate the sociolinguistic implications of literacy and orthographic choices, demonstrating Pe?h-oe-ji's role as a linguistic counter to Sinocentric narratives and its embodiment of the complex relationships between literacy, identity, and resistance. This study provides valuable insights into literacy studies, particularly on the relationship between literacy and identity.