The ethanolic extract from the fruits of Emblica officinalis Gaertn (Euphorbiaceae) was investigated to evaluate its possible ameliorating effects, on the L-thyroxine (L-T4) induced hyperthyroidism and on hepatic lipid peroxidation in mice. While an increase in serum T3 (triiodothyronine) and T4 (thyroxine) concentrations, and in a thyroid dependent parameter, hepatic glucose 6-phospatase (glu-6-pase) activity was observed in L-T4 (0.5 mg/kg/d) treated animals, simultaneous oral administration of the plant extract at a dose of 250 mg/kg/d (p.o.) for 30 days in hyperthyroid mice reduced T3 and T4 concentrations by 64 and 70% respectively as compared to a standard antithyroid drug, propyl thiouracil (PTU) that decreased the levels of the thyroid hormones by 59 and 40% respectively. The plant extract also maintained nearly normal value of glu-6-pase activity in hyperthyroid mice. The plant extract also decreased hepatic lipid peroxidation (LPO) and increased the superoxide dismutase (SOD) and catalase (CAT) activities in hyperthyroid mice, exhibiting its hepatoprotective nature. Our findings suggest that the test material may potentially ameliorate the hyperthyroidism with an additional hepatoprotective benefit.