Tumor necrosis factor, a regulatory cytokine, is extremely important signaling protein in the immune system. Among TNF family, TNF-alpha, TNF-beta are most the significant family members. Receptor of TNF namely TNFR1 and TNFR2 stimulates two different signaling pathways. TNFR1 signaling induces apoptosis pathway. Conversely, TNFR2 signaling triggers cell survival pathways. In this paper, we discuss about the TNF family with special reference to TNF-alpha/TNF-beta, different hypothesis related to autoimmunity and role of TNF, structure of TNF-alpha/TNF-beta, distribution and normal activity in human body of TNF, receptors and signaling pathway for drug targeting. Finally, we also discuss about the therapy for autoimmune diseases and immune-mediated inflammatory diseases (IMIDs) using small molecules or therapeutic proteins.