Inhibiting the major characteristics of alcoholic fatty liver (AFL) such as lipid accumulation, oxidative stress and apoptosis is a promising strategy of treating AFL. Diallyl trisulfide (DATS) is the major constituent isolated from garlic, which shows promise in the treatment of chronic liver disease. However, the effects of DATS on ethanol-induced liver injury and the related mechanisms remain unclear. The aim of this study was to evaluate the potential protective effects of DATS on AFL and the potential mechanisms. A single intragastric dose of ethanol was given to rats in vivo, while ethanol-stimulated LO2 cells were used as an in vitro model. Our results demonstrated that DATS prevented ethanol-induced injury, as indicated by the reduced activities of aspartate transaminase (AST) and alanine aminotransferase (ALT) in the serum and culture medium, and inhibition of cell apoptosis. Furthermore, DATS reduced hepatic steatosis by up-regulating the expression of peroxisome proliferator-activated receptor-alpha (PPAR-α) and down-regulating the expression of sterolregulatory element binding protein 1c(SREBP-1c). In addition, DATS alleviated ethanol-induced oxidative stress by enhancing non-enzymatic antioxidant and enzymatic antioxidants contents and by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA). These data collectively revealed that DATS protected ethanol-induced liver injury by inhibiting lipid accumulation and oxidative stress.