Marine animals provide a wide range of bioactive compounds that may offer new and innovative therapeutic tools for use in various diseases. In this study, the bioactive compounds in the extracts of Acanthopleura vaillantii (chiton) were identified, their antioxidant property assayed and the hepatoprotective activity evaluated in a carbon tetrachloride-induced hepatotoxicity model in mice. The gas chromatography-mass spectrometry (GC-MS) analysis identified mostly the polyphenolic compounds. The antioxidant assay showed that the chiton extract had radical scavenging activity. Intraperitoneal injection of the chiton extract in mice increased the hepatic enzymes and albumin content at the dose level of 10 mg chiton /kg of body weight. While administration of 20 mg chiton extract in mice was with the normalized serum albumin (Alb), alanine aminotransferases (ALT) and aspartate (AST). The histological examination of the liver sections from the 10 and 20 mg chitons treated groups showed substantial attenuation of the degenerative cellular changes, recovery from necrosis and reversal of liver fibrosis induced by the carbon tetrachloride intoxication.