The present invention relates to a method for manufacturing a composite sheet comprising an aerogel sheet, which comprises: a step (S10) of preparing a fiber sheet (10); a step (S20) of laminating the aerogel sheet (30) on each of both surfaces of the fiber sheet (10); and a step (S30) of applying heat and a pressure to the aerogel sheet (30) and the fiber sheet (10), which are laminated, to bond the sheets to each other and to manufacture the composite sheet (40) in which the aerogel sheet (30), the fiber sheet (10), the aerogel sheet (30) are laminated.