Purpose: This study aims to examine how digital multilingual practices are employed on social media to negotiate identity from a critical discourse perspective. It focuses on how language choice, code-switching, and multimodal resources function as strategic tools for self-presentation, audience management, and identity construction in digital environments. Subjects and Methods: The study adopts a qualitative design grounded in Critical Discourse Analysis. The data consist of 120 publicly accessible multilingual social media posts collected from Instagram, X (formerly Twitter), and Facebook over a three-month period, as well as 15 semi-structured interviews with active multilingual social media users. Data were analyzed through a multi-stage procedure involving linguistic categorization, functional discourse analysis, identity indexing analysis, multimodal analysis, and thematic analysis of interview data. Results: The findings reveal that multilingual practices are patterned and intentional rather than random. Intra-sentential code-switching emerges as the most prominent practice, reflecting integrated multilingual expression. English is predominantly associated with professional, global, and aspirational identities, while local languages are used to express emotional authenticity, cultural belonging, and relational closeness. Users construct hybrid identities by strategically combining linguistic and visual resources. Interview data indicate a high level of metalinguistic awareness, highlighting the role of audience orientation and platform norms in shaping language choice. Conclusions: The study concludes that digital multilingual practices function as socially meaningful and multimodal resources for identity negotiation, shaped by power relations, language ideologies, and global–local dynamics in contemporary social media discourse.