Abstract:Background: Globally maternal mortality remained a public health challenge. Institutional delivery ensures safe birth which reduces maternal mortality and morbidity. This study aimed to assess determinants of institutional delivery among mothers who gave birth in the last one year. Methods: A community-based cross-sectional study was conducted during May 16 to 28, 2016 in Dejen woreda. Multistage sampling technique was used for selection of 361 participants and collected data were entered and analyzed using Statistical package for social sciences (SPSS) version 20. Multiple logistic regression was employed to identify factors associated with the institutional delivery at p-value <0.05` and to control the confounders. Results: Institutional delivery service utilization was 71.7%. Educational status, age and residence of the mother, having antenatal care visit/frequency of ANC visit, gravidity and husband's preference were independent predictors of institutional delivery service utilization. Conclusion and recommendation: Many women gave birth at health institution in Dejen Woreda. Younger age, having secondary and above educational status and urban residents, having 4 or above ANC visit, primiparaous and husband's preferred health facility had significantly associated with increased institutional delivery. Empowering women, ensuring all women to receive ANC visit according to the recommended number of visit, improving the quality of information on skilled delivery and enhancing partner's involvement, as well as increasing accessibility of health facilities in the rural areas, could increase institutional delivery service utilization.