BACKGROUND: Non-institutional delivery is one of the major reasons that results in high mortality rates for a mother and her neonate. The World Health Organization estimates that only 43% of mothers have access to skilled delivery services. A recent Ethiopian Mini Demographic Survey indicated that more than half of Ethiopian women have given birth non-institutionally. This shows that maternal health remains a major public health challenge in Ethiopia, irrespective of the government's measures for institutional delivery. So, the aim of this study was to assess the practice of non-institutional delivery and its associated factors among women who gave birth in the study area. METHODS: A community-based cross-sectional study was carried out on 260 study participants from June 1 to July 1, 2022, in Boloso Bombe Woreda. Data collection was done using a structured questionnaire, and systematic sampling techniques were used to select the study subjects. The data was entered into the EPI data version 3.1 and analyzed using SPSS version 25. The adjusted odds ratio, along with 95% confidence intervals, was used, and the level of statistical significance was declared at a P-value of 0.05. RESULT: Out of 260 women interviewed, 252 (97%) pregnant women participated in the interview. The prevalence of non-institutional delivery among study participants was 68.7% (95% CI: 63.1-72.9). Mothers who were a daily laborer [AOR = 6.6;95%CI(3.6(1.2-11.2), last pregnancy planned [AOR = 0.4; 95%CI (0.4(0.2-0.8)), an absence of antenatal care contacting history [AOR = 3.3; 95%CI (1.3-8.6)], respondents' knowledge on the labor complication [AOR = 3; (95%CI); 3.5(2.2-6.1)], and place of first delivery [AOR = 8.7 95%CI(3.2-23)] were factors that significantly associated with practice of non-institutional delivery. CONCLUSION: This study indicated that the majority of study participants practiced non-institutional delivery in this study area. Thus, we strongly recommend that all responsible bodies take immediate action, such as community health education on pregnancy-related complications, encouraging ANC visits, and raising awareness of the advantages of preventing non-institutional delivery in order to reduce non-institutional pregnancy practices and improve the factors identified.