The invention discloses a metallic oxide/conducting polymer crossed sheet flower array and a preparation method thereof, the metallic oxide/conducting polymer crossed sheet flower array is prepared through that oxidized metal salt scattered on a growth medium catalyzes a reaction monomer to generate polymerization reaction and the metal salt itself generates hydrolysis reaction and is further annealed. The metal salt is simultaneously used as catalyst for preparing the conducting polymer and a precursor for preparing the metallic oxide, the polymerization reaction and the hydrolysis reaction generates simultaneously, thus, the metallic oxide and the conducting polymer are combined closely through coating and embedding rather than being simply mixed as two substances. The conducting polymercoats the metallic oxide, thus, direct contact between the metallic oxide and electrolyte can be isolated, and the metallic oxide is prevented from being dissolved in the electrolyte in an oxidationreduction process and forming irreversible capacitance. Additionally, shape of crossed sheet flowers has relatively higher specific surface area, array distribution provides an ion fast transmission channel, and consequently, conductivity of materials is improved.