<p>This study examines the belief in "k̄hwạỵ" (spirit essence) in Northeastern Thailand, analyzing its significance through folkloric perspectives. The researcher uses an emic approach that involves a structural analysis concerned with understanding the internal cultural framework of a specific society, wherein researchers draw on indigenous sources and cultural informants to identify constructs that are unique to that culture's worldview and belief system. The research examines two traditional ceremonies: the Bāyṣ̄rī s̄ū̀ K̄hwạỵ and S̄̀xn k̄hwạỵ which represent fundamental spiritual practices in the region. Through qualitative research methodology, including in-depth interviews with ritual practitioners and participant observation, this study investigates how these ceremonies manifest across three dimensions: individual, social, and supernatural. The research reveals that the concept of spiritual essence remains deeply integrated into Northeastern Thai culture, particularly in rural communities. These beliefs serve as mechanisms for psychological support, social cohesion, and cultural preservation. The ceremonies demonstrate remarkable adaptability, evolving to accommodate contemporary contexts while maintaining their traditional significance, as evidenced by their incorporation into modern institutions and practices. The findings indicate that spirit essence beliefs continue to influence daily life, decision-making processes, and social interactions. Despite modernization, these beliefs persist as vital components of Northeastern Thai cultural identity, functioning as sophisticated systems for managing uncertainty, maintaining psychological well-being, and fostering community relationships. This research contributes to understanding the role of traditional spiritual beliefs in contemporary society and their significance in preserving cultural heritage.</p>