Background and Objectives: The purpose of this study is to evaluate the role of MRI as an investigative modality in white matter diseases and to document clinic-radiological value in early diagnosis and management. This was done by studying the MR findings of different white matter diseases at our hospital with clinical presentation correlation along with most prevalent diseases and their location identification. Materials and Methods: Forty patients with a strong clinical suspicion of demyelinating disorder were evaluated by MRI using 1.5 Tesla (GE Optima MR360) scanners in a prospective study period of 1 year after ethical approval at GIMS, Patna, Dept. of Radiology. Patients were referred from neuromedicine department. Results: PRES (MS) was the most common white matter disease encountered in our one year study after ethical approval. Out of 40 cases, 16(40%) cases presented with altered sensorium, seizure and visual disturbances among which most of cases were of nephrotic syndrome and few hypertensive post delivery female patients. Among 16 cases of PRES,all 16(100%) cases showed posterior parieto-occipital periventricular and deep white matter involvement on MRI as T2/FLAIR axial images hyperintensity and T1 hypointensity. Conclusion: MRI is the modality of choice for early lesion detection, disease progression and in follow up cases in both subclinical and clinical settings due to its multiplanar images and better resolution. Therefore, early management for better patient cure is possible.