A semiconductor package and a manufacturing method thereof are provided. The semiconductor package includes a substrate, a semiconductor element, a package body and a conductive part. The substrate has an electrical contact. The semiconductor element is disposed on the substrate. The package body covers the semiconductor element and defines a through hole from which the electrical contact is exposed. Wherein, the package body includes a resin body and a plurality of fiber layers. The fiber layers are disposed in the resin body and define a plurality of fiber apertures which is arranged as an array. The conductive part is electrically connected to the substrate through the through hole.