The post-Cold War world politics presents impetus and propels states to update their International Relations thinking in many ways irrespective of their power status in the world politics. As Bangladesh does not elude the impetus created by the global politics of 21st century, this paper argues that formulating grand strategy can contribute to update International Relations thinking of Bangladesh. Once seemingly obsolescence idea has become the cynosure of scholars in the 21st century. Tracing the evolution of the idea of grand strategy, this paper illustrates how formulation of grand strategy has descended from great powers to middle powers and, therefore, argues that the idea has become applicable for all states. The article, therefore, explores the rationales of Bangladesh to have grand strategy in the 21st century. The article argues that as the kernel of grand strategy is to serve grand national interests; So, Bangladesh can have declared grand strategy to safeguard and augment enduring national interests of Bangladesh. This article attempts to fill up the knowledge gap of nonexistence of grand strategy scholarship in Bangladesh and contributes to update Bangladeshs International Relations thinking by applying it.