Objective：To evaluate the predictive value of placental intravoxel incoherent motion（IVIM）MRI parameters and fetal brain volume in predicting VLBWI in FGR. Methods：A retrospective analysis was conducted on 23 pregnant women with FGR， categorized into VLBWI group（n=8）and non-VLBWI group（n=15）based on birth weight. We compared brain structures as a percentage of intracranial volume and placental IVIM parameters［true diffusion coefficient（D），pseudo-diffusion coefficient（D^* ）， perfusion fraction（f），and placental area］between the two groups. Receiver operating characteristic（ROC）curve analysis was used to assess the predictive efficacy of each parameter for VLBWI. Results：The placental D value in the VLBWI group was lower than that in the non-VLBWI group［（1.38±0.04）×10^-3 mm² /s vs.（1.44±0.07）×10^-3 mm² /s，t=-2.109，P=0.047］，and the placental area was smaller in the VLBWI group［（155.84 ± 34.69）cm² vs.（200.41 ± 47.95）cm² ，t=-2.315，P=0.031］，while the percentage of lateral ventricle volume relative to intracranial volume was greater in the VLBWI group［（3.00 ± 0.55）% vs.（2.53 ± 0.33）%，t=2.591，P=0.017］. The areas under the ROC curve for placental D value，placental area，and lateral ventricle as a percentage of intracranial volume were 0.767，0.783，and 0.792，respectively. Combining the fetal lateral ventricle as a percentage of intracranial volume，placental D value，and placental area improved the ROC curve area to 0.892. Conclusion：Placental IVIM parameters and fetal brain volume may serve as potentially effective imaging markers for distinguishing VLBWI in cases of FGR.