BACKGROUND:The influence of socio-cultural factors on institutional birth is not sufficiently documented in Ethiopia. Thus, this study explores socio-cultural beliefs and practices during childbirth and its influences on the utilization of institutional delivery services. METHODS: A qualitative study was conducted in three regions of Ethiopia through eight focus group discussions (with women) and thirty in-depth interviews with key informants which included health workers, community volunteers, and leaders. The data were analyzed thematically. RESULTS:  The study identified six overarching socio-cultural factors influencing institutional birth in the study communities. The high preference for traditional birth attendants (TBAs) and home as it is intergenerational culture and suitable for privacy are among the factors. Correspondingly, culturally unacceptable birth practices at health facilities (such as birth position, physical assessment, delivery coach) and inconvenience of health facility setting to practice traditional birth rituals such as newborn welcoming ceremony made women avoid health facility birth. On the other hand, misperceptions and worries on medical interventions such as episiotomy, combined with mistreatment from health workers, and lack of parent engagement in delivery process discouraged women from seeking institutional birth. The provision of delivery service by male health workers was cited as a social taboo and against communities' belief system which prohibited women from giving birth at a health facility.  CONCLUSIONS: Multiple socio-cultural factors and perceptions were generally affected utilization of institutional birth in study communities. Hence, culturally competent interventions through education, re-orientation, and adaptation of beneficial norms combined with women friendly care are essential to promote health facility birth.  KEYWORDS: Ethiopia, Institutional delivery, Traditional birth attendants, Socio-cultural factors.