Background The utilization of facility-based health care was among the means to tackle the transmission of the COVID 19 and protection of better health. However, reluctance to the utilization of facility-based health care has been reported to be a major problem everywhere in the globe including Ethiopia. Purpose To assess the utilization of facility-based health care and associated factors among adults in Oromia regional state, Ethiopia. Participant and Methods: Community-based cross-sectional study was conducted using a quantitative approach among the randomly selected 2751 adults aged 18 years and above. Data was collected using an interviewer-administered structured questionnaire. The collected data were entered into Epi info version 7.2.0.1 and analyzed using STATA 15. Descriptive statistics was computed. Bivariate and multivariable binary logistic regression analyses were done to determine the association between the study variables. Odds Ratio with its 95%CI was calculated and P-Value