Cervical spondylotic myelopathy (CSM), commonly seen in the elderly, is caused by the chronic compression of the spinal cord induced by cervical disc degradation. Magnetic resonance imaging (MRI) can clearly reveal spinal canal stenosis, morphology and signal changes of compressed spinal cord, but it falls short in demonstrating the slight changes and microstructure of the spinal cord and is not capable of quantitative analysis. Diffusion tensor imaging (DTI) is a new MRI technique which can display the water molecule diffusion characteristics in the nerve fiber cells, with the evaluation parameters mainly including the apparent diffusion coefficient (ADC) and the fractional anisotropy (FA). Moreover, it can clearly display the fiber bundle of the spinal cord with the diffusion tensor tractography (DTT), making it currently the only non-invasive way to trace the white matter fiber bundle. Studies have reported that DTI parameters compared with routine MRI is more sensitive in early diagnosis, neuronal function evaluation, and prognosis prediction of CSM. DTT can clearly display the morphology and dynamic changes of spinal nerve bundles, evaluate the neuronal function and predict the post-operation prognosis. There are still limitations for spinal DTI, such as lack of standard method for measuring and analyzing DTI parameters, and whether DTT can reflect the true pathological status of spinal cord. Here we reviewed the development of DTI technology and its role in CSM.