Abstract: Diffusion tensor imaging (DTI) is a recently developed functional MRI technique based on the random thermal motion of water molecules within tissues along different axes, which allows the quantificationally assessment of the shape, direction, arrangement, tightness, myelinization of the white matter fiber tracts in neural tissues in vivo. DTI is being widely used in the various domains of ophthalmology. In this article, the principles of DTI methodologies are explained, and several applications in ophthalmology are introduced, including optic neuropathy (ischemia, traumatic optic neuropathy, optic neuritis),  glaucoma, as well as visual development and amblyopia.