A porous material including a composite oxide body containing calcium oxide, iron oxide, and silica, and a plurality of inter-connecting microchannel structures is provided. A preparing method of porous material is further provided. With the inter-connecting microchannel structures of the porous material and the advantages of high porosity and large specific surface area, the porous material has a bright prospect in the fields of catalysts, filters, adsorption materials, and fuel carriers.