Abstract: A method for preparing an ultra-light-weight (ULW) proppant usable in the oil and gas industry. The method uses silane coupling agent and organic acid to modify silica fume (SF) to obtain modified SF that is lipophilic and hydrophobic. The modified SF is used as inorganic phase, and the polymerizable monomer is used as organic phase, and the organic-inorganic composite microspheres are obtained through suspension polymerization. The ULW proppant is obtained by drying, screening, and pre-oxidization of the composite microsphere. The ULW proppant has a density of about 1.109 g/cm3-1.278 g/cm3, which is close to that of water, a crushing rate of <5% at 52 Mpa, and a crushing rate of <7% at 69 Mpa. In the oil and gas industry application, water or salt water can be used to replace the high viscose guanidine gum as carrier, thus reduced cost of fracturing, and reduced environment pollution.