PROBLEM TO BE SOLVED: To provide a composite sheet of nonwoven fabric/fiber web, an absorber product and a method for manufacturing the composite sheet. SOLUTION: In the composite sheet wherein the nonwoven fabric layer and the fiber web layer are mutually bonded, the composite sheet has high density and is constituted of a plurality of first network regions reduced in thickness and a second network region relatively low in density with respect to the first network regions. The nonwoven fabric layer has a smooth surface and the fiber web layer has a bulky surface. The unit of weight of the nonwoven fabric layer is 10-50 g/m<2> and the Gurley permeability of the whole of the composite sheet is not more than 3 sec. The fiber web layer has a fineness of 1.5-12d and contains fibers with a fiber length of 100 mm or less selected from PE type, PP type, PET type, nylon type and acrylic type synthetic fiber staples and a mixture of them as a main component.