This study investigates the obstacles to language sustainability in Bangladesh, which boasts a wealth of linguistic diversity, and proposes a comprehensive plan to support this variety. The study begins with an examination of Bangladesh’s linguistic demographics, highlighting the multitude of languages spoken by the country’s various ethnic communities. It then delves into the historical context of language movements in Bangladesh and illustrates how language serves as a crucial marker of identity and unity. Subsequently, this research explores the socioeconomic, political, and educational factors that contribute to language endangerment and change. It discusses the consequences of these changes on cultural identity, transmission of knowledge, and community well-being. This study proposes a comprehensive framework for language sustainability in Bangladesh, emphasising five key components: documentation and revitalisation of endangered languages, implementation of comprehensive multilingual education policies, utilisation of modern technology in language preservation, promotion of cross-cultural understanding through exchange programs, and national policy support for language rights and diversity. These initiatives aim to enhance linguistic sustainability, foster social cohesion, and empower marginalised communities. This study argues that by addressing these challenges and adopting these strategies, Bangladesh can secure a sustainable linguistic future and preserve its diverse cultural heritage.