Background: - Vaginal Birth after Cesarean section (VBAC) is associated with shorter maternal hospitalizations, less blood loss and fewer transfusions, fewer infections and fewer thromboembolic events than cesarean delivery Objective: - To assess factors associated with successful vaginal birth after one previous cesarean section in pregnant women who opted for trial of labor in alert hospital Methods: - A health facility based cross sectional Retrospective study design will be employed, in Addis Ababa city administration, Alert Hospital. Using single proportion formula a total of 411 participant were selected by simple random sampling, the data was collected by means of structured check list. The data were entered, coded and analyzed using statistical package for social science (SPSS) version 25. Descriptive statistics of the collected data were performed for most variables such as socio-demographic, obstetric and health behavioral variables in the study using standard statistical parameters: percentage, means and standard deviation. To identify the factors associated with successful vaginal birth after one previous cesarean section, bivariate and multivariate logistic regression analyses were performed. Variables with p value < 0.05 during the bivariate analysis were included in the multivariate analysis to see the effect of confounding factors. Odds ratio with 95% confidence intervals and statistical significance P<0.05 were considered. Results: - A total sample of 411 participants were involved in the study, making response rate of 98.6%. In the study participant who were parity of 3-4, and ≥ 5 had 22.3 times and 15 times increase the successful VBAC than participant of having para two ( AOR=22.3, 95%CI=17.72, 28.24 and AOR=15, 95%CI=6.93, 32.59), whose primary c/s was done with indication of failure progress of labor had 98.7% less likely of successful VBAC than those of indication with fetal distress (AOR=0.013, 95%CI=0.002, 0.098) Conclusions: - This study concludes that factors associated with successful VBAC are associated with socio-demographic, obstetric and fetal characteristics analyzed for patients to be counseled for or against trial of labor.