In order to evaluate the anticancer activity of 1,4-naphthoquinone derivatives, several 1,4-naphthoquinone derivatives were newly synthesized and subjected to mouse leukemia p-388 cell line by MTT cytotoxicity assay. Among the several 1,4-naphtho-quinone derivatives, YC-001 has showed the most potent anticancer activity. To determine the safety of YC-001, hematotoxicity was tested. YC-001 induced hemolysis increased with both concentration and time dependent manner. The mechanism of hemolysis considered to be the generation of oxygen free radicals and lipid peroxydation of erythrocyte membrane which composed of phospholipids. Also methemoglobin, oxidized form of hemoglobin, was formed by YC-001.