The invention discloses a catalytic distillation device for preparing methanol, and a use method thereof. A storage mechanism comprises a supporting plate and a vertical plate, a vertical rod is fixedly connected to the top of the supporting plate, a column is fixedly connected to one side of the vertical plate, a containing groove is formed in the top of the column, and a first through hole part is formed in the outer surface of the column. The invention relates to the technical field of methanol preparation. According to the catalytic distillation device for preparing methanol, and the use method thereof, under the cooperative use of the supporting plate, the vertical plate, the vertical rod, the column , the containing groove, the first through hole part, a second through hole part, a first connecting plate and a limiting hole, a catalyst is intensively placed in the containing groove, and when a sealing cover is opened, the catalyst can be taken out and replaced only by taking out the vertical plate, so the device is convenient to use, and solves the problem that when the catalyst is used in an existing catalytic distillation device, the catalyst is generally and directly placed in the catalytic distillation device, so that the subsequent catalyst is very inconvenient to take out and replace.