Background: The extended post-partum period is the twelve months after delivery, which is a very critical time for mothers to ensure a safe birth interval. Many women do not realize that they are at risk of pregnancy during the postpartum period and the importance of birth interval. Birth interval more than two years reduces maternal and child mortality and give a better health for the mother and the child. Because of this assessing post-partum contraceptive utilization and the determining factors is crucial. Hence, the study was conducted to determine contraceptive utilization and identify factors which affect post -partum contraceptive utilization Methods: A community based cross sectional study was implemented among 422 women who gave birth one year prior to the study period in wukro town. The total sample size was allocated to the three kebeles proportionally. Systematic random sampling technique was used to select study subjects. Data were collected by interviewer administered structured questionnaire. The data were coded and entered using EpiData version 3.1 and transported to Statistical Package for Social Science version 20 for analysis. Binary and multivariable logistic regressions were fitted. Odds ratio with 95% confidence interval was used to measure strength of association. Results: A total of 422 women were enrolled in this study. Nearly half (48.6%) of the women were using contraceptive. Multivariable logistic regression showed that prenatal counseling [AOR 3.06(95% CI; 1.30, 7.22)], menses returned [AOR 3.99(95% CI; 1.96, 8.11)] and resuming sexual activity [AOR 5.96(95% CI; 2.67, 13.3)] were positively associated with utilization of postpartum contraceptive. Conclusions: Postpartum contraceptive use was low. Strengthening prenatal family planning counseling and improving women’s awareness about the return of their fertility after childbirth are suggested to improve family planning utilization in extended postpartum period.