To determine whether anti-tumor necrosis factors induce clinical response and remission in patients with Crohn's disease, PUBMED, OVID, and SCOPUS databases were searched for studies investigated the efficacy of anti-tumor necrosis factors on CD. Data were collected from 1966 to 2005 (up to 31 December). Types of outcome investigated were response (decrease in CDAI score >/=70 points) and remission (CDAI score </=150 points) 2 and 4 weeks after drug administration. The criteria for inclusion of studies in this analysis were exposure of patients with CD to any therapeutic dosage of any anti-tumor necrosis factors (infliximab, cetrolizumab, CDP870, CDP571, etanercept, onarcept). The results showed that anti-tumor necrosis factors have improved only clinical response 2 weeks after administration of these drugs statistically, but their effects on clinical remission after 2 weeks and response and remission after 4 weeks have not been significant. It seems that anti-tumor necrosis factors are not effective for induction of response and remission in patients with Crohn's disease.