Type 2 diabetes mellitus (T2-DM) is a chronic metabolic disorder characterized by high blood glucose levels. T2-DM patients suffer from many complications, such as diabetic fatty liver and diabetic nephropathy. The liver, the pivotal organ involved in both glucose and lipid metabolism, is primarily damaged in T2-DM patients, especially in those with high levels of blood lipid. In this study, the hepatoprotective activity of ginsenoside Rg1 was investigated in a T2-DM rat model. The results revealed a potent hepatoprotective effect of ginsenoside Rg1. This effect was primarily mediated by the antiapoptotic effect, inhibition of JNK activity, and suppression of inflammation after ginsenoside Rg1 treatment. Ginsenoside Rg1 also lowered the blood glucose level and insulin resistance index in T2-DM rats. Moreover, the blood lipid profile (total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels) and liver function (aspartate transaminase and alanine transaminase levels) improved after ginsenoside Rg1 treatment. The aforementioned hepatoprotective effects of ginsenoside Rg1 in the T2-DM rat model suggests its clinical potential as an adjuvant drug for T2-DM therapy, especially for T2-DM patients with fatty liver disease.