Abstract： Objective:To evaluate the efficacy of cerebral-placental-uterine ratio(CPUR)in predicting late-on-set fetal growth restriction(FGR).Methods:From May 2020 to May 2021,1255 women with singleton pregnancy who underwent prenatal examinations at the University of Hong Kong Shenzhen Hospital were selected for fetal growth and Doppler measurements at 35-37 +6 weeks of gestation.Pregnant women with birth weight of newbo-rns＜the 10th percentile were the FGR group.The pulsatility index(PI)of uterine artery(UtA),umbilical artery(UA)and fetal middle cerebral artery(MCA)were analyzed separately and in combination.ROC curve was used to analyze the cerebral-placental-uterine ratio(CPUR),cerebral-placental ratio(CPR),cerebral-uterine ratio(C-UtA)for predicting late-onset FGR;and to evaluate the sensitivity,positive and negative predictive value and of CPUR in the prediction of late-onset FGR.Results:The area under the curve(AUC)of CPUR,CPR,C-UtA and mean UtA-PI for FGR grope were 0.88,0.86,0.84 and 0.72.Under certain cut-off values and 87% specificity,the specificity of CPUR,CPR,C-UtA and mean UtA-Pifor predicting FGR group was 43.2%,46.6%,39.8% and 23.9%,respectively.The positive predictive values of CPUR,CPR,C-UtA and mean UtA-PI,UA-PI for predicting FGR group were 90.5%,71.9%,83.3%,63.6%and 5.2%,respectively.Conclusions:CPUR is more effective in predicting late onset FGR than CPR,C-UtA and mean UtA-PI.It can effectively increase the detection rate of fetal growth restrictionand reduce the FGR risk.