The magnetic resonance (MR) features of a 67-year-old woman with a surgically and pathologically proved primary leiomyosarcoma of the liver studied at 1.0 T, using T1- (TR/TE = 450/15), and T2- weighted (TR/TE = 2200/45 to 90) spin-echo (SE) images, are described. On T1-weighted SE images, the tumor was well defined, was slightly heterogeneous, and displayed hypointensity to the adjacent hepatic parenchyma, with an area displaying hyperintensity. On T2-weighted SE images, the tumor was encapsulated, was heterogeneous, and displayed marked hyperintensity.