After exploring the theories on abdominal mass of Orthodox Medical Record written by Yu Tuan，this paper concludes Yu Tuans academic characteristics of the abdominal mass.The etiology and pathogenesis of the abdominal mass include exogenous disease of six climate exopathogens，internal damage induced by the excessive seven emotions，improper diet and overtiredness.The pathogenesis is internal damage of the spleen and stomach; as mentioned as “the fundamental of the abdominal mass is the spleen and stomach”.The treatment rule of Yu Tuan was following the therapy theory of Yellow Emperor，which emphasized on differentiation of yin and yang，qi and blood，deficiency and excess，cold and heat.Yu Tuan followed the therapeutic methods of Zhu Danxi，quoted the prescriptions of Liu Hejian，and applied the following treatments including reinforcement and elimination in combination，simultaneously application of both cold and hot drugs.The herbs that act as invigorating for deficiency，activating blood circulation to dissipate blood stasis，regulating the flow of qi were frequently used.