The present application discloses a fore-attached composite structure for diaper including a substrate layer composited by a polymer film, the surface of the substrate layer being composited with a fiber layer of a thermoplastic polymer and having a number of projections, wherein the fiber layer composited on the projections is fluffy and the fiber layer formed at the recess between each pair of projections is in a dense status. Since the substrate layer composited by the polymer film has the characteristic of being light, soft, and permeable, the fiber layer of a thermoplastic polymer has a soft hand-feel and can be firmly connected via hook&loop fastener.