A three-dimensional gap-filled preform and a method of forming a three-dimensional gap-filled preform. The preforms comprise a base section of all integrally woven layers, a portion of that base separated into three sections, the outer two sections comprising integrally woven layers, and the middle section comprising an integrated gap filler. The integrated gap filler may comprise a center section of one woven layer, independently woven layers, integrally woven layers, or a plurality of layers of warp fibers that are not interwoven with weft fibers. The layers of the integrated gap filler compress or crumple up in the middle section and fill the formed gap or gaps, while the woven layers of the outer sections are folded to form the shape of the preform.