A semiconductor package and a manufacturing method thereof are provided. The semiconductor package includes a semiconductor die an insulating encapsulation laterally covering the semiconductor die. The semiconductor die includes a semiconductor substrate, a plurality of conductive pads distributed over the semiconductor substrate, a plurality of conductive vias disposed on and electrically connected to the conductive pads, and a dielectric layer disposed over the semiconductor substrate and spaced the conductive vias apart from one another. A sidewall of the dielectric layer extends along sidewalls of the conductive vias, the conductive vias are recessed from a top surface of the dielectric layer, and a sloped surface of the dielectric layer is connected to the top surface of the dielectric layer and the sidewall of the dielectric layer.