The invention discloses a method for preparing an antimony-doped tin dioxide aerogel three-dimensional electrode through normal pressure drying and belongs to the technical field of electrocatalytic electrode preparation, and by means of the method, electrocatalytic oxidation efficiency of traditional two-dimensional electrodes is improved. The method comprises the steps of firstly, preparing antimony-doped tin dioxide aerogel through a sol-gel method, then conducting methyl silanization with tetraethoxysilane, replacing hydroxy on the surface of alcogel with silicon oxygen bond, forming a silicon oxide frame structure among tin oxide oligomer, and conducting solvent exchange, normal pressure drying and calcination to obtain the antimony-doped tin dioxide aerogel which is of a mesoporous structure and large in specific surface area. The antimony-doped tin dioxide aerogel prepared through the method has a three-dimensional network structure formed by crosslinking of nanoparticles and is high in specific surface area and large in number of electrochemical activity points, the defects that aerogel prepared through a supercritical drying method is high in energy consumption and dangerousness, easy to break in water and the like are overcome, and high application value is achieved in the electrochemical catalysis field.