A method for preparing silicon carbide powder according to an embodiment of the present disclosure includes the steps of: mixing a silicon (Si) source with a carbon (C) source including a solid carbon source or an organic carbon compound, and a silicon dioxide (SiO2) source, to form a mixture; and allowing the mixture to react, wherein the molar ratio of silicon dioxide in the silicon dioxide source to the sum of silicon in the silicon source and carbon in the carbon source is 0.01:1 to 0.3:1.