Background Obstetric fistula is abnormal passage way between the vagina and bladder or rectum and it has the most devastating effects on physical, social and economic levels and represents a major public health issue of thousands of women, which failed to provide accessible and appropriate intrapartum care for women within developing country, particularly in Ethiopia. Therefore, we tried to assess the awareness and its associated factors of obstetrics fistula among pregnant mothers attending antenatal care clinics.Method A health institutional based cross-sectional study was employed from March 4–29/2019 among 413 pregnant women. The data was collected by systematic random sampling technique and entered into a computer using Epi data 3.5, edited and analyzed using Statistical Package of Social Sciences 23.0 version. Bivariate and multivariate logistic regression analyses was employed to estimate the crude and adjusted odds ratio with confidence interval of 95% and p value of less than 0.05 considered statically significant.Results The study identified that 39.5% with 95% confidence interval (34.6-44.6%) of pregnant women were had good awareness about obstetrics fistula. Multivariate logistic regression analysis showed that, living in urban AOR=1.98, 95% CI=1.07-3.69], attending formal education [AOR=2.11, 95%CI=1.06-4.12], having history antenatal care [AOR=3.87, 95%CI, =1.60-9.68] and childbirth at health institution [AOR=7.10, 95%CI=2.52-2.02] were have a positive association with awareness of obstetrics fistula. On the other hand, occupation of the respondents: house wife [AOR=0.30, 95% CI=016-0.57] and merchants [AOR= 0.41, 95% CI=0.20-0.91] were have a negative association with awareness of obstetrics fistula.Conclusion This study showed that awareness of obstetrics fistula was low. Residency, education and occupation of the women, having history of antenatal care and childbirth at health institution was significantly associated with awareness of obstetrics fistula. Still there is a gap on awareness of obstetrics fistula; therefore, it is good to emphasis on providing information on maternal health care issues, particularly about obstetrics fistula.