Malignant transformation of hepatocellular carcinoma (HCC) occurs through repetitive liver injury in a context of inflammation and oxidative DNA damage. A spectrum of natural sesquiterpenoids from curcuma oil has displayed antioxidant, anti-inflammatory and anti-carcinogenic properties. The aim of the study was to investigate the hepatoprotective and anti-HCC effects of curcuma oil in vivo and in vitro. Mice were pretreated with curcuma oil (100 mg/kg) for 3 days, then treated with Concanavalin A (30 mg/kg). The hepatic tissue was evaluated for histology, CD4+ cell, interferon-γ, apoptosis, lipid peroxidation, 8-hydroxy-deoxyguanosine and MnSOD. C57L/J mice were treated with curcuma oil and 107 Hepa1-6 cells directly inoculated into liver lobes. The effects of curcuma oil on cell growth and cell death were evaluated. In addition, MnSOD, HSP60, catalase, NF-κB and caspase-3 were also investigated in the Hepa1-6 cells treated with curcuma oil. Pretreatment with curcuma oil significantly attenuates inflammation and oxidative damage by Concanavalin A. Treatment with curcuma oil can decrease the incidence of HCC. Curcuma oil inhibits cell growth and induces cell death in Hepa1-6 cells. Curcuma protected mice with hepatic injury from inflammatory and oxidative stress. Curcuma oil can inhibit hepatoma cell growth in vivo and in vitro.