Spontaneous intracranial hypotension (SIH) is an important cause of headache mainly associated with spinal cerebrospinal fluid leakage. We herein report the case of a 51-year-old man who developed SIH after swimming. Brain magnetic resonance imaging (MRI) showed a transient high-intensity lesion in the splenium of the corpus callosum (SCC), in addition to bilateral subdural hematomas (SDH) and pseudo-subarachnoid hemorrhage on brain computed tomography. The splenial lesion disappeared and SDH improved after an epidural blood patch. This case emphasizes that transient SCC lesions could coexist with SIH and that SIH should be considered in the differential diagnosis of SCC lesions.