Piceatannol, a natural derivative of resveratrol, has been shown to exert similar anti-oxidant and anti-inflammatory effects as resveratrol. However, it remains unknown whether piceatannol has hepatoprotective effect against acute liver injury. In this study, we investigated the in vivo effect of piceatannol on D-GalN/LPS-induced fulminant hepatic failure (FHF), and its in vitro effect on ER stress-inducing drug thapsigargin (TG)-induced proinflammatory cytokines production and ROS release. Our results indicated that piceatannol markedly decreased the mortality rate, reduced the serum levels of alanine transaminase and aspartic aminotransferase, ameliorated the liver damage induced by D-GalN/LPS in mice. In addition, piceatannol reduced the expression of proinflammatory cytokines, including TNF-α, IL-1β and IL-6, the expression of ER stress markers CHOP and phosphorylated-IRE1α, and the generation of oxidative stress in D-GalN/LPS-treated mouse liver. In vitro results were consistent with in vivo observations, demonstrating that piceatannol suppressed the secretion of proinflammatory cytokines, inflammasome activation and the production of ROS induced by TG with or without LPS priming in J774A.1 macrophages. Our study proposes piceatannol as a promising medication for preventing acute liver failure and the mechanisms may be related to its inhibitory effects on ER stress, inflammation and oxidative stress.