A 55-year-old woman was admitted because of a tumor located in the ventral region of S4 of the liver, just beneath the diaphragm. A CT scan revealed the round tumor to be delineated as a 33 mm in size, with an outer capsule. The tumor was visualized as concentric circles which presented high-, low-, and high- signal patterns on T2-weighted MRI. It also presented a triphasic pattern in which the border and the central part were not contrasted as a low signal pattern, while the middle part was contrasted as a high signal pattern by T1-weighted enhanced imaging with Gd-DTPA. Angiography revealed that the tumor did not originate from the liver but from the diaphragm, so it was surgically resected as a primary diaphragmatic tumor. We report a schwannoma which originated from the diaphragm, that showed characteristic imaging findings and required to be distinguished from a liver tumor.