Over the last 20 years, theoretical debates have become an increasingly conspicuous part in the broader field of International Relations Theory. If we are in need of an adequate theory that provides a set of plausible and testable answers to questions about theoretical diversity under specified conditions, the existing theory, in term, does not suffice. This paper attempts to provide a comprehensive perspective to understand the existing diversity of research approaches and theoretical concepts of international relations. To this end, the objective of this study is to establish an analytical framework for the theoretical diversity of international relations by the unifying concept to understand the phenomenon theoretical diversity. Noise of these discussed can be resolved through existing diversity, but only attempting to describe a theoretical debate that could be resolved in the future.