Cosmopolitanism and global peace are fundamental concepts in contemporary thought that have garnered significant attention in both Western and Eastern spheres. These concepts exhibit meaningful differences in the Eastern and Western intellectual traditions, particularly in terms of philosophical outlooks and worldviews. Therefore, this article aims to conduct a comparative analysis of the thoughts of Martyr Motahari and Immanuel Kant regarding cosmopolitanism and peace. The central question of this article is: how are the ideas of cosmopolitanism and democratic peace explained from the perspectives of Martyr Motahari and Immanuel Kant? In response, it can be hypothesized that cosmopolitanism, from Martyr Motahari's perspective, is based on three fundamental principles: the epistemology of humanity, society, and the world. In contrast, Kant views it through the lens of public law, dividing it into three categories: the right of governance, national rights, and international rights. Regarding peace, both thinkers agree that republican political systems, being people-centered, are advocates of peace, and are not driven by the pursuit of power or war, as war inherently has a destructive nature, and human societies suffer from its consequences. The findings of this research suggest that achieving global peace and cosmopolitanism is possible through interaction, dialogue, and collective cooperation.