The purpose of this study was to explore the conception, implementation, and challenges of adult learning principles in an integrated functional Adult education program of North Mecha Woreda. To understand whether adult learning principles are being implemented in integrated functional adult education programs such as facilitators‟ conceptions of adult learning principles, implementation of adult learning principles in IFAE programs, and major challenges hindering facilitators in implementing adult learning principles were assessed. The study deployed Qualitative research, social constructive research paradigm, and case study design. Observation, Interview, and FGD were data gathering tools used in this study. As sufficient data collected with such tools, data was analyzed thematically in narration. Facilitators and learners of the investigated areas, the woreda IFAE expert were data sources of this study. Since learners were high in number (430), 28 learners selected with purposive sampling, there was a facilitator within a center facilitators were selected with purposive sampling techniques and Woreda IFAE expert too was selected with comprehensive sampling techniques. Both facilitators were conceiving adult learning principles differently. Commonly both of whom were not familiar with the term andragogy and andragogical assumptions too. Both facilitators conceiving adult learning principles; except the urban facilitator in the ability to implementing learners self – concept, both of whom were implementing adult learning principles (motivation to learning, need to know, learners prior experience, orientation to learning, readiness to learning) in IFAE processes. With Woreda IFAE expert supervision, monitoring, and guidance, both center facilitators were implementing adult learning principles in challenging situations of facilitators‟ shortage/lack of training, well-equipped facilitation center problems, stakeholders' support, lack of learning environments were potent challenges of facilitators