MRI(magnetic resonance imaging) had been the most up-to-dated modality in evaluating white matter disease in recent years, shereas US (ultrasonogram) has been used extensively in diagnosis of neonatal PVL (peri-ventricular leukomalacia) conventionally. We evaluated the diagnostic value of MRI by reviewing the MR findings and correlation of MR and US of PVL in 11 preterm infants. Evaluation criteria were MR signal intensity and discrimination of PVL on each pulse sequences and comparision between MR and US findings performed simultaneously, on the extent of PVL, size of the largest cyst and detectability of hemorrhagic lesion, MR findings of 1 cases of PVL were of low signal patterns on T1W1 (T1 weighted image) in 7, low signal patterns on PDWI (proton density weighted image) in 9, iso signal patterns on T2W1(T2 weighted image) in 8 and low signal patterns on STIR (short time inversion recover) in 7 cases. The lesions of 11 PVL were well discriminated in all 11 cases of T1W1, 7 cases of STIR, 5 case of PDWI and 2 cases of T2W1. The lateral ventricle was diffuse dilated (n=1) and focally dilated (n=3) in atrial area. In the comparative study, MR presented more extensive lesions in 7 cases, larger cysts in 6 cases out of 7 PVL and more definitive hemorrhage in 3 cases out of 4 cases than sonography, In conclusion, MR was more valuable than sonography in evaluating the extent of lesions, size of the largest cystic lesion and detetion of hemorrhage. T1WI and STIR images were more useful in detection of PVL than T2WI and PDWI.