A magnetic resonance imaging (MRI) apparatus and a method of processing an MR image are provided. The MRI apparatus includes a scanner configured to acquire a first image that is a T1-weighted image and a second image that is a fluid attenuated inversion recovery (FLAIR) image by performing an MRI scan on a brain. The MRI apparatus further includes an image processor configured to determine a white matter region in the second image based on the first image and the second image, and detect a white matter hyperintensity (WMH) region in the determined white matter region. The MRI apparatus further includes an output interface configured to display the detected WMH region and a change in the WMH region over time.