A semiconductor package includes a first layer including a first semiconductor chip and a first through via, a first redistribution layer disposed on a surface of the first layer, and including a first-first wiring and a second-first wiring, and a second layer including a second semiconductor chip, and stacked on the first layer. The first semiconductor chip includes a first-first buffer, and the first-first buffer is electrically connected between the first-first wiring and the second-first wiring.