The present invention relates to a transgenic pig that expresses sTNFR1-Fc, wherein a gene encoding sTNFR1-Fc, which is a fusion protein of the extracellular domain of human soluble tumor necrosis factor receptor (sTNFR1) and an immunoglobulin Fc region, is introduced; a method for preparing the same; an organ isolated from the transgenic pig; a somatic donor cell line inserted with sTNFR1-Fc gene; a method for preparing a blood sample comprising sTNFR1-Fc; and a method for preparing human sTNFR1-Fc from the blood sample of the transgenic pig. As the transgenic pig can suppress immune response and inflammatory response by secreting an inhibitory substance that suppresses the activity of TNF-α in blood, it can be effectively used for xenograft. Furthermore, since the transgenic pig has a blood type O, it can be transplanted for suppressing inflammatory response, regardless of a blood type of recipient.