1,25 Dihydroxyvitamin D (1,25(OH)D) modulates inflammation and immune responses. Deficiency of 1,25(OH)D was found to be associated with the risk of cancer, cardiovascular disease, osteoarthritis, infections, and autoimmune diseases. This study evaluated the effect of 1,25 dihydroxyvitamin D 1,25(OH)D on thioacetamide (TAA)-induced acute liver injury in rats.Rats were treated with either saline or 1,25(OH)D (0.30 μg/kg; orogastrically) for 15 d. Starting from day 13, TAA (200 mg/kg; intraperitoneally) was given for 3 d. On day 15, all rats were euthanized. Liver and blood samples were collected.TAA caused severe damage, increased lipid peroxidation with reductions in endogenous antioxidants, increased apoptosis, increased production of reactive oxygen species, and elevated inducible nitric oxide synthase (iNOS), and nuclear factor kappa B (NF-κB) expression in liver. Extent of damage was decreased by 1,25(OH)D (P < 0.01). 1,25(OH)D attenuated the increase in malondialdehyde (P < 0.01), increase in myeloperoxidase (P < 0.01), increase in chemiluminescence levels (P < 0.05) and apoptotic activity (P < 0.001). Elevated liver iNOS and NF-κB expression in TAA group was also reduced by 1,25(OH)D (P < 0.001, for iNOS; P < 0.001, for NF-κB). TAA group revealed high serum aspartate transaminase and alanine transaminase (ALT) activities (P < 0.01, for aspartate transaminase; P = 0.08, for ALT) and reduced albumin levels (P < 0.01) compared with control. 1,25(OH)D had no statistically significant effect on these parameters.1,25(OH)D provides protection against hepatic injury in a rat model of TAA-induced hepatotoxicity via suppression of inflammatory reaction, oxidative stress, and apoptosis.