This investigation delves into the realm of graphic design in post-World War II Japan, undertaking a comprehensive examination of diverse thematic elements such as the integration of pop culture, the resurgence of Japanese cultural aesthetics, and the pervasive influence exerted by Western paradigms. Central to the inquiry is an exploration of the multifaceted factors that have contributed to the evolution of graphic design during this transformative period, contextualized within the rich tapestry of cultural heritage and contemporary expressions. Methodologically, the study employs semi-structured interviews as its primary mode of inquiry, subjected to rigorous thematic analysis. A cohort of 14 participants, renowned experts in the domains of pop culture and Japanese poster art, lends depth and expertise to the analysis. Utilizing a meticulous three-step coding process, the study meticulously identifies key themes, providing a nuanced depiction of the defining characteristics, features, and influences shaping post-WWII graphic design in Japan. The findings underscore the prominence of vibrant colour schemes, a harmonious fusion of traditional and modern elements, and the pervasive use of symbolic imagery as hallmark attributes. Moreover, the narrative trajectory of design evolution is revealed to be intricately intertwined with the prevailing influences of pop culture, which in turn play a pivotal role in shaping consumerist behaviours. The visual lexicon of post-WWII Japan emerges as profoundly shaped by the burgeoning impact of Western art and foreign cultural exchanges. This study bears significance for practitioners in marketing, design, and cultural institutions, serving as a foundational resource elucidating the myriad dynamics and practical implications inherent in the field. Notably, the study offers novel theoretical insights that are actionable for professionals and scholars alike, facilitating a deeper exploration of the complex interplay between culture, design, and identity.