Background: Labor and delivery is a normal physiologic process that most women experience without complications. Improving the health of mothers and children through well-organized institutional delivery service is central to achieve reduced maternal and child morbidity and mortality. So, factors that underlie the level of institutional delivery service utilization need to be investigated, especially in areas where little is known about the problem. This study is an attempt to fill this gap by find out magnitude of facility delivery and identify major determinant factors of institutional delivery service utilization that affect service utilization. Methods: Community based cross sectional study was done on 512 samples from to March 2022. Sampling survey was carried out in 8 rural kebeles to identify mothers who gave birth with in the past one year. Mothers were selected by using systematic random sampling technique. Data were collected using a pre-tested and structured questionnaire by face-to face interviewing, EPI-Data was used to enter the data and SPPS version 23.0 was employed for analysis. Simple and multivariate binary logistic regressions were used with cutting points to determine candidate variables and identify factors associated with outcome variables respectively. Results: In a survey of 512 women participants, 313 (61.1%) had their last birth in health institution. From the result of the binary logistic regression analysis, we were able to figure out that education status of husband [(AOR = 2, 95%t CI = (1.0–3.3)], ANC visit during recent pregnancy [(AOR = 22, 95% CI = (11–44.6)], personal assist in health facility [(AOR = 0.47, 95 % CI = 0.37–0.61)], Delivery Practice during pregnancy [(AOR = 2.7, 95 % CI = 1.2–6.4)], attitude of mothers delivered at health facility towards institutional delivery [(AOR = 0.46, 95% =(0.23–0.86)] and government employee status[AOR=1.6, 95%CI (1.2-2.4)] were found to be significantly associated with institutional based health facility delivery. Conclusion and recommendation: Although, the prevalence of institutional delivery is still low in the study area compared to government initiatives. Antenatal care visits, educational status of husband, at health facility visit health personnel assisted you recently; participant occupational status, delivery Practice and attitude mothers delivered at health facility were found to be significantly associated with low institution based health delivery of the service. Strategies which focus on increasing Antenatal care uptake, maternal monthly panel discussion, and increasing husband educational level help to increase health facility delivery service utilization. Key words: Institutional delivery, Utilization, Reproductive women, Guba, Ethiopia.