To easily manufacture each radio wave absorption layer with uniform thickness even in a radio wave absorber having a complex shape with curvature when a plurality of the radio wave absorption layers are formed on one side of a radio wave reflection layer.

In this manufacturing method of the radio wave absorber, when the radio wave absorber having the radio wave reflection layer is formed on one side of the radio wave absorption layer, a sheet for hydraulic transfer is floated on a liquid surface, where the sheet has a water-soluble and water- swelling base film and the plurality of radio wave absorption layers for transfer, and the radio wave reflection layer to be transferred is inserted from the upper section, thus utilizing hydraulic pressure for transferring the plurality of radio wave absorption layers for transfer onto the surface of the radio wave reflection layer.