Abstract:Magnetic resonance imaging（MRI）has apparent dominance in nasopharyngeal carcinoma (NPC) diagnosis, staging, the plan of radiotherapy target and assessment of efficacy because of its high-contrast of parenchyma and muli-parameters imaging. Especially diffusion-weighted imaging (DWI) developed in several years, it can provide qualitative and quantitative information at the cellular level about tumor cellularity and the integrity of cell membranes, which is valuable for tumor detection, cervical lymph nodes metastases, systemic transfer, monitoring and predicting the treatment response of nasopharyngeal carcinoma.