The invention discloses a method for large-scale preparation of a transition metal oxide porous microsphere, and belongs to the technical field of synthesis of nano materials. The key points of the technical scheme of the invention are as below: dissolving polyhydric alcohol in an organic solvent under room temperature to form a uniform solution; adding the transition metal salt to the uniform solution under the condition of stirring, and uniformly mixing to obtain a precursor solution; transferring the precursor solution for drying in a spray dryer, and collecting the powder at the bottom of a drying tower by a cyclone separator; placing the powder in a muffle furnace, heating to 350-650 DEG C at heating rate of 1-8 DEG C / min, calcining 0.5-5 h and naturally cooling to room temperature obtain the transition metal oxide porous microsphere. The invention realizes the large-scale preparation of transition metal oxide porous microsphere; spray drying can realize continuous process in nanomaterial preparation; and the prepared transition metal oxide porous microsphere can be used directly, without crushing or grinding.