Percutaneous ethanol injection therapy (PEIT) has been widely practiced in the treatment of liver tumors, especially of hepatocellular carcinoma (HCC). Histopathologic examinations, findings in imaging modalities and serum tumor marker levels have shown a remarkable anticancer effect of this procedure. In addition, PEIT has achieved considerably high long-term survival rates. For small HCC, PEIT has been generally accepted as an alternative to surgery. Here we will describe PEIT from the viewpoints of patient selection, technique, various evaluation procedures of efficacy, long-term results, side effects and complications, and relationship with other therapies.