To provide a silicon carbide based porous compact and a method of manufacturing the same which is containing a silicon carbide grain and a silicon nitride grain, excellent in heat resistance, corrosion resistance, chemical resistance, strength, heat shock resistance, and preferable for collecting and eliminating particulates.

The method of manufacturing the silicon carbide based porous compact is characterized in that a compact formed of 70-98 mass% mixed powder composed of 70-95 mass% silicon carbide grain of 10-100 μm mean grain diameter, 5-30 mass % metallic silicon grain of 1-50 μm mean grain diameter, and 2-30 mass % pore generating agent, is heat treated in a nitrogen atmosphere so as to nitride the metallic silicon grain.