Hepatic fibrosis is the wound-healing process of chronic hepatic disease that leads to end-stage of hepatocellular carcinoma and demolition of hepatic structures. EMT has been identified to phenotypic conversion of the epithelium to mesenchymal phenotype that occurred during fibrosis. Smad decoy oligodeoxynucleotide (ODN) is a synthetic DNA fragment containing complementary sequence of Smad transcription factor. Thus, this study evaluated the anti-fibrotic effects of Smad decoy ODN on carbon tetrachloride (CCl4)-induced hepatic fibrosis in mice. As shown in histological results, CCl4 treatment triggered hepatic fibrosis and increased Smad expression. On the contrary, Smad decoy ODN administration suppressed fibrogenesis and EMT process. The expression of Smad signaling and EMT-associated protein was markedly decreased in Smad decoy ODN treatment mice compared with CCl4-injuried mice. In conclusion, these data indicate the practicability of Smad decoy ODN administration for preventing hepatic fibrosis and EMT processes.