Objective: The low cerebropalcental ratio(CPR) has reported to be associated with obstetric intervention due to fetal distress in low risk population. The aim of this study was to evaluate a value of CPR as a routine screening for predicting an obstetric intervention during labor in unselected population in the third trimester. The primary outcome of this study was to compare of rate of cesarean delivery during labor according to the value of CPR and the secondary outcome was to compare the adverse perinatal outcome. Methods: Retrospective chart review of singleton pregnancies who were delivered after 34 weeks gestation from January 2017 to June 2018 at a single hospital was performed. CPR was computed by dividing middle cerebral artery and umbilical artery pulsatility index. Low CPR was defined by 10th percentile of the study population. The CPR was reviewed of record of within 1 week before delivery. Exclusion criteria were elective cesarean section without labor and major fetal anomaly. The variables were appropriately analyzed using Chi-square test, Fishers exact test and t-test. Statistical analysis was performed by SPSS 22.0 and p value<0.05 was considered significant. Results: A total 291 women were included in this study. Mean age of study population was 33.3±4.7 years and primiparous women was 57.4%. There was no significant difference for rate of cesarean section during labor between low CPR and normal CPR (40.8%, vs 55.2%, p=0.143). There were no significant differences for adverse perinatal outcomes between the groups. Conclusion: Although CPR has been suggested for component of routine examination for assessment of fetal well-being, efficacy of CPR as a routine screening for predicting obstetric intervention during labor in unselected population in the third trimester was limited. Acknowledgements: This study was supported by research grants from Hanmi Pharmaceutical Co., Ltd.