TNFα (tumor necrosis factor-alpha) plays a critical role in the pathogenesis of inflammatory diseases including rheumatoid arthritis and Crohn's disease. Infliximab is a monoclonal antibody that recognizes human TNFα. Clinical trials have been persuasive that infliximab is effective and far superior to the conventional drug therapy in various inflammatory diseases. Combination of infliximab plus methotrexate is effective in patients with active rheumatoid arthritis who have not responded adequately to traditional disease-modifying anti-rheumatic drugs, and has produced significant improvement in clinical, radiographic, and functional outcomes. Infliximab is also an important treatment option in patients with active Crohn's disease who have not responded to conventional therapy and in those with this disease who have fistulae. Moreover, infliximab treatment has resulted in effective suppression of ankylosing spondylitis, psoriasis and ocular inflammation in patients with refractory uveoretinitis due to Behçet's disease. Thus, biologics targeting TNFα have revolutionized the therapy of inflammatory diseases. Here, the current status of clinical application of anti-TNFα biologics is reviewed by describing the clinical outcome of infliximab and future prospects of biologics are discussed.