Aim: The present study was performed to investigate the effect of Aesculus hippocastanum (AH; Venoplant®) on concanavalin A (ConA)-induced acute liver injury and explore the mechanism in mice. Methods: ConA (20 mg/kg) was administered via tail vein injection to induce hepatic damage. The groups of AH (Venoplant®) were given at 65.8, 131.6, and 263.2 mg/kg by oral gavages for 20 days. The serum levels of aspartate transaminase (AST), alanine aminotransferase (ALT), total protein (TP), and albumin (Alb) were determined by automatic biochemical analyzer, and the Alb/globulin (A/G) ratio was calculated. Tumor necrosis factor-α (TNF-α) and IFN-γ levels were assayed by enzyme-linked immunosorbent assay. The liver tissue was attained by hematoxylin and eosin, and the histopathological changes were calculated. The cell apoptosis was assayed by terminal dUTP nick-end labeling. The malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) content of liver tissue were assayed by related kits. The activity of caspase-3 was detected by spectrophotometry. The expressions of cytochrome c, Bax, Bcl-2, c-Jun N-terminal kinase (JNK), and p-JNK were detected by western blot. Results: The results showed that the levels of ALT, AST, IFN-γ, and TNF-α in AH (Venoplant®) groups were significantly lower than those in ConA-injured group, while the levels of TP, Alb, and A/G were significantly higher. The SOD and GSH levels were significantly increased, and the MDA level was decreased; liver histopathology was changed consistently with the serological indicators, AH (Venoplant®) treatment significantly reduced the pathological damage and cell apoptosis; while in AH (Venoplant®) group, the expressions of cytochrome c, caspase-3, Bax/Bcl-2 ratio, and p-JNK were significantly decreased. Conclusion: AH (Venoplant®) could significantly protect the ConA-induced acute liver injury in mice via inhibition of reactive oxygen species and JNK pathway.