To improve the recognition of reversible splenial lesion syndrome (RESLES).One adult case of reversible splenial lesion syndrome was reported.The clinical and imaging features of RESLES were summarized and the related literatures were reviewed.A 51-year-old male patient presented with fever prior to RESLES onset.Headache was the only neurological manifestation,which occurred 3 days after fever.The IgM antibody for influenza virus of type B was detected.Cerebrospinal fluid test was normal expect for sight higher pressure.The symptom of headache was completely alleviated after the treatment of ganciclovir only for two days.The splenium of the corpus callosum presented with isolated long ovoid abnormal signal on T2-weighted 、fluid-attenuated inversion recovery and diffusion-weighted imaging when the MRI scan was implemented after the onset of 9 days.The abnormal lesion disappeared only 5 days later when the patient was received repeated MRI scan.During the whole Process,we have found the fact that the clinical symptom was rapidly alleviated and the abnormal signal in the splenium of the corpus callosum was reversible within short time.Case reports of audlt RESLES were rare,so clinical practitioners had insufficient recognition of this disease.Headache is the commonest symptom.MRI shows reversible lesion in the splenium of the corpus callosum,which demonstrate high signal on DWI.