Despite having more than 200 environmental laws and policies in Bangladesh, the overall ecological situation is almost beyond control. Relying on both primary and secondary sources of data, particularly the legal texts, this study delves into analysing the legal frameworks of Bangladesh pertaining to wildlife and biodiversity conservation in the Sundarbans mangrove forest (SMF). This study finds that the lack of implementation of stringent provisions is one of the key reasons for the failure to successfully conserve biological diversity in the SMF. The other reason that heavily accelerates environmental crimes in Bangladesh is the less severe punishment compared to other crimes. This study result reveals that the Animal Welfare Act 2019 imposes a mere BDT 10,000 (USD 116) for harming any animal. This study also finds that the Environment Court Act 2010 strives to expand environmental governance in every district, but the absolute authority of the Department of Environment (DoE) and its limited resources hinder such lavish expansion. Although the government has revised many outdated laws and policies and enacted new laws such as Bangladesh Environment Conservation Act 1995 (2023), Forest Act 2023, and Forest Conservation Act 2023, evidence indicates that most of the provisions were not successfully implemented due to overlaps with other laws and loopholes within the laws. In addition, complex bureaucratic systems significantly hamper the administration system in forest management. Furthermore, the Director General (DG) of the DoE’s sole authority often sparked concerns regarding the transparency and accountability of this department. Therefore, this paper examines the domestic legal system of Bangladesh for conserving biodiversity in the SMF.