The invention discloses a novel preparation method of a large-pore-volume SiO2 material. The method comprises the following steps: preparing a Na2SiO3 solution by adopting Na2SiO3.9H2O and deionized water, and dropwise adding HNO3 into the Na2SiO3.9H2O solution while stirring until a gel is precipitated; aging the gel for a period of time at a certain temperature; washing out Na ions in the gel bycentrifugation, soaking the obtained product in an ammonium salt solution with a certain concentration for a period of time, and then taking out the gel; and drying the gel by using a spray dryer ata certain air inlet temperature and injection flow rate. In the preparation process of the SiO2 material, aging treatment and ammonium salt activation are carried out after the silica gel is preparedthrough an acid-alkali neutralization reaction, and finally, the SiO2 material with rich pore volumes and high specific surface area is prepared. The yield of the SiO2 obtained by the method is high.The method is simple in technological process, greenness and environment friendliness are achieved, and the production period is short.