Tissue distribution, excretion and fate of T-2 toxin, a potent cytotoxic mycotoxin of Fusarium spp., were examined in mice and rats by using tracer and chromatographic techniques. Orally administration T-2 toxin to mice and rats was rapidly eliminated into the feces and urine with a ratio of 4-5:1. In mice, the toxin distributed in the liver, kidney and other organs without showing a specific accumulation. In rats, the toxin was excreted into the feces partly as HT-2 toxin, T-2 toxin and 2 unknowns and was excreted into the urine partly as HT-2 toxin, 8-hydroxydiacetoxyscirpenol (neosolaniol) and 3 unidentified metabolites. Toxicological significance of the hepatic and derm floral carboxyesterase (EC 3.1.1.1) was discussed in regard to the specific deacetylation of T-2 toxin.