The competencies of public health professionals serve as the cornerstone for curriculum development ensuring that educational programs are pertinent efficient and attuned to the requirements of both the public health workforce and the communities they serve. This study endeavors to investigate the knowledge competency of public health professionals in Thailand with the intention of refining the suitability of knowledge competency for curriculum development tailored to the needs of public health professionals in Thailand. Employing a qualitative study, the study conducted semi-structured interviews with 17 university lecturers in public health programs in Northeastern Thailand. The data collected were transcribed and analyzed using content analysis. The findings elucidate that the lecturers articulated a core knowledge content pertinent to public health professionals in Thailand delineated across five principal themes and thirteen subjects within the public health curriculum. These themes encompassed: 1) Epidemiology and disease prevention (comprising two subjects), 2) Health promotion and community health (comprising four subjects), 3) Research methods in public health and biostatistics (comprising two subjects), 4) Public health administration, health system, and laws (comprising three subjects), and 5) Environmental health and occupational health and safety (comprising two subjects). Subsequently, this study scrutinized five core courses to formulate a model curriculum for public health. The proposed model curriculum is intended for application in both planning and the development of the public health workforce, fostering interdisciplinary learning and nurturing public health professionals rooted in the authentic context of Thailand.