A method of manufacturing a semiconductor package includes forming a plurality of trenches at a first surface of a silicon substrate, forming a conductive pad inside each of the plurality of trenches, forming a redistribution layer on the first surface of the silicon substrate, forming an external connection terminal on a first surface of the redistribution layer, removing the silicon substrate to expose each conductive pad, mounting a semiconductor chip to be connected to the conductive pads, and forming an encapsulant to cover at least one surface of the semiconductor chip.