Background - Ethiopia is one of the countries which suffer with highest unintended pregnancies and unsafe abortion. The aim of this study was to assess the utilization of post-abortion family planning and associated factors among women seeking abortion service in Asella town health facilities 2019.Methods: A facility based cross-sectional study design was conducted among women who came for abortion service from July 15 to October 15, 2019. Two hundred seventy-six participants were included using systematic random sampling technique. Both descriptive and logistic regression analysis were conducted. In multivariate analysis, variables which had p-value < 0.05 was considered as significantly associated with the outcome variable. Results: Postabortion family planning utilization among study participants was 146 (53.7%) (95% CI=47.4, 59.2). Formal education (AOR=4.45: 95% CI: (1.18, 16.74) , previous history of abortion (AOR=0.35; 95% CI: (0.14, 0.85), positive attitude (AOR=2.62; 95% CI: (1.09, 6.27), counseled on post abortion family planning utilization (AOR=3.12; 95% CI: (1.30, 7.51) were significantly associated with post abortion family planning utilization.Conclusions: In this study, nearly fifty percent of the respondents did not utilize Postabortion Family Planning (PAFP). Educational status, history of pervious abortion, decision when to have a child, attitude toward PAFP utilization and counseling about PAFP were significantly associated with post-abortion family planning use. The health care providers who give abortion service should give counseling for all women who get abortion service. More accents should be given to misperception of PAFP to change the negative attitude of utilization of PAFP.