The invention relates to a method for preparing Al mixed with ZnO nanosheet array by adopting a pulsed electromagnetic field, which is as follows: an FTO conductive sheet glass is placed in an ultrasonic cleaner for cleaning; the mixed solution I of zinc acetate, ethanol amine and ethylene glycol monomethyl ether is dripped on the conductive sheet glass, and is uniformly coated through a spin coater and heat treated to form a ZnO film thereon; the FTO conductive sheet glass coated with the ZnO film is put into a reaction kettle, the mixed solution II formed by aluminium nitrate, zinc nitrate and hexamethylene tetramine as well as deionized water is filled into the reaction kettle, the pulsed electromagnetic field treatment is applied to the reaction system in the reaction kettle, the kettle is moved to a constant temperature oven for hydrothermal reaction after the treatment, and the sediment on the surface of the glass is washed and dried after the hydrothermal reaction, so as to obtain the Al mixed with ZnO nanosheet array. The method is simple to operate, has low energy consumption, enables the orientation of the nanosheets to be identical, has higher verticality, enables the nanosheets to be neatly arrayed, has big specific surface area, facilitates electron transport when serving as the photoanode, and improves the efficiency of the dye sensitized solar cell.