Ganweikang tablet (GWK) is a traditional Chinese prescription and has been clinically used in treating liver diseases for decades. Although GWK has been shown to exert potential therapeutic effect for hepatotoxicity protection, the underlying biological mechanisms are still not well clarified. In the present study, the compositional analysis of GWK was performed by HPLC analysis, and the hepato-protective effects of GWK were assessed in H2O2-stimulated acute oxidative injured HL-7702 hepatocytes in vitro. As a result, 7 components in GWK were quantified to be 0.06 ± 0.01% (calycosin), 0.46 ± 0.02% (calycosin-7-glucoside), 0.13 ± 0.01% (liquiritin), 0.17 ± 0.02% (glycyrrhizic acid), 0.45 ± 0.02% (forsythoside A), 0.07 ± 0.01% (5-O-methylvisammioside) and 0.45 ± 0.02% (forsythin), respectively. Furthermore, GWK (100, 200 and 400 μg/mL, 24 h) dose-dependently alleviated HL-7702 hepatocytes from H2O2 (200 μM, 2 h)-induced cell apoptosis by decreasing the intracellular reactive oxygen species (ROS) generation and malondialdehyde (MDA) level, as well as the cellular aminotransferases (ALT and AST) activities. GWK increased the expressions of HO-1, NQO1 and Nrf2, while suppressing the expression of KEAP1 in H2O2−stimulated HL-7702 cells. A specific Nrf2 inhibitor, ML385, was further employed to investigate the regulation of Nrf2 in HL-7702 cells stimulated by H2O2. In addition, the activation of MAPKs (JUN, ERK and p38) was simultaneously detected in H2O2−stimulated HL-7702 cells. In conclusion, GWK exerted potential therapeutic effect to protect hepatocytes from acute oxidative injury through activating the Nrf2/HO-1 and MAPKs pathways.