The invention discloses a zinc vanadate with a porous hierarchical structure. The chemical formula of the zinc vanadate is Zn2V2O7. The hierarchical structure is formed by inserting sheet layer structures, and the surface is coarse and porous. A preparation method is also disclosed. The preparation method adopts a simple hydrothermal method, wherein ammonium metavanadate and zinc acetate are usedas raw materials, polyethylene glycol is used as a surfactant, the reaction temperature is 160 DEG C for 24h, and an obtained product is calcined at 450 DEG C for 5h, and the obtained sample is zinc vanadate. The zinc vanadate is used as the electrode material of a super capacitor. The zinc vanadate has high specific capacity and good cycle stability. The zinc vanadate of the invention is uniformin shape, experimental operation is simple, raw materials are non-toxic and easily available and good material performance is achieved when the zinc vanadate is used for the super capacitor.