The in vitro antioxidant activity and in vivo protective effect of total triterpenoids in Fuji apple pomace (TTAP) on CCl4-induced acute liver injury in mice wereinvestigated. TTAP was isolated and purified by ultrasonic-assisted extraction and macroporous resin column chromatography, respectively. Using ascorbic acid (Vc) as control, the 2,2-diphenyl-1-picryl-hydrazyl (DPPH?); 2,2’-azino-di-(3- ethylbenzthiazoline-6-sulphonic acid (ABTS+?), and hydroxyl (?OH) scavenging abilities of TTAP were measured to evaluate its antioxidant activity. A CCl4-induced acute liver injury mouse model was established. Subsequently, aspartate transaminase (ALT) and aspartate transaminase (AST) activities in serum as well as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, malondialdehyde (MDA) content and interleukin-6 (IL-6) content in mouse liver homogenates were measured by biochemical assays. TTAP showed lesser extent of in vitro antioxidant ability compared with Vc. The in vivo study showed that ALT and AST activities in serum declined significantly and the largest decline was more than 48% when compared with the model group. Additionally, SOD and GSH-Px activities in liver homogenates significantly increased, with the highest increase of 69%. MDA and IL-6 contents declined significantly, with the largest decline of 43%. TTAP thus exhibited significant protective effect on CCl4-induced liver injury mouse model and the underlying mechanism may be related to in vivo free-radical scavenging and regulation of serum enzymes, as well as activity and content of antioxidant enzymes.