Objective To investigate the morphological and signal-changing characteristics of placental MRI in fetal growth restriction. Methods A total of 100 cases of fetal growth restriction in pregnant women examined by MRI from July 2015 to February 2018 in our hospital were analyzed retrospectively. The uterus of the pregnant woman was examined by sagittal, crown and axial scans. The maternal image data was analyzed, the placenta-related values were measured. Results The placental with fetal growth restriction in fetus showed a thickening a spherical shape of the placenta. The area of the placenta uterus attachment surface was reduced, the placenta of attachment at the edge became circle bluntness, some were accompanied by placental infarction, expressing as a diffuse signal change in the central high signal edge on the HASTE sequence; After placental hemorrhage, it expressed as small platelet low signal shadow under placenta in HASTE sequence; there was subchorionic hemorrhage, expressing as small platelet low signal shadow under the chorion in HASTE sequence. There was no statistical difference between the expression of placental MRI and postpartum pathological expression in pregnant women (P>0.05); 19 children died after delivery, the placental volume of the newborn in the survival group was higher than that in the death group, the difference was statistically significant (P<0.05); The maximum thickness of the placenta and the ratio of the maximum thickness of the placenta to placenta volume in the survival group were lower than those of the control group (P<0.05). There was no significant difference between the placental volume of fetal growth restriction placenta MRI and the placenta after production (P>0.05). Conclusion MRI examination of placenta with fetal growth restriction has a variety of characteristic imaging performances and can be used for clinical diagnosis.