The invention discloses a low-silicon prebaked anode and a preparation method thereof, and relates to the technical field of aluminum electrolysis in nonferrous metal metallurgy. The low-silicon prebaked anode is prepared by adding fluorine-contained inorganic salt in anode raw materials; the adding quantity of the fluorine-contained inorganic salt is 0.1-2% of the total quantity of the anode raw materials; the anode raw materials include 82-86 mass% of carbon aggregate and 14-18 mass% of binding agent; and the low-silicon prebaked anode controls the silicon content in a lower range to satisfy the demand of electrolytic aluminum on high-quality anode. The preparation method comprises the following steps: the fluorine-contained inorganic salt is added in the carbon aggregate for full mixing and preheating; then, the binding agent is added in the mixing process for forming and roasting to prepare the low-silicon prebaked anode; and the preparation method can reduce the silicon content of the prepared prebaked anode to control in a range of 100-200 ppm.