A waterproof sheet which is for application to a site to be waterproofed in order to prevent rainwater infiltration thereinto and retard deteriorations which proceed with time, the waterproof sheet comprising: a base layer that comprises a silicone rubber composition reinforced with reinforcing fibers and that has physical properties including high strength; and a pressure-sensitive silicone adhesive layer that has been formed on one surface of the base layer and that has a low hardness and is highly tacky. The waterproof sheet provided by the present invention less breaks than conventional waterproof sheets because of the reinforcement layer, and can conform to cracks or dislocations occurring in the surfaces to which the waterproof sheet has been applied, due to the pressure-sensitive adhesive layer formed on one surface. Since the waterproof sheet includes silicones as main components and is hence excellent in terms of weatherability, heat resistance, and freeze resistance, this waterproof sheet can retain the function required of waterproof sheets, over a longer period.