3,4,4'-Trichlorocarbanilide (TCC), uniformly labeled with 14C in the monochloro ring, was administered to rats, rhesus monkeys, and humans. Radioactive materials in the plasma and urine of all three species and in the bile of rats and monkeys were separated by high performance liquid chromatography. The chromatography showed great similarity between the monkey and the human. Principal metabolites common to all species were the sulfate and glucuronide conjugates of 2'-, 3'-, and 6-hydroxy-TCC. The rat also produced the glucuronide and sulfate conjugates of 2',6-dihydroxy-TCC. The major urinary excretion products found in humans and monkeys were the N- and N'-TCC glucuronides.