The role of scintigraphic imaging has moved from the detection of lesions to the tissue-specific characterization of lesions over the past 2 decades. Major advances in nuclear medicine imaging include: 1) positron imaging, 2) improved instrumentation, such as the use of multidetector (dual or triple head) gamma cameras for single photon emission computed tomography, and 3) development of numerous new radiopharmaceuticals for positron or single photon imaging ( labeled glucose analogue, amino acids, fatty acids, hormones, drugs, receptor ligands, monoclonal antibodies, etc). These advanced have resulted in a significantly improved efficacy of radionuclide techniques for the evaluation of various of focal gepatic tumors is reviewed in this article with an emphasis on the clinical applications of various tracer studies and imaging findings. ( Korean J Nucl Med 1998;32;211-24)