A semiconductor package includes a substrate and an interposer disposed on the substrate. The interposer comprises a first surface facing the substrate and a second surface facing away from the substrate. A first logic semiconductor chip is disposed on the first surface of the interposer and is spaced apart from the substrate in a first direction orthogonal to an upper surface of the substrate. A first memory package is disposed on the second surface of the interposer. A second memory package is disposed on the second surface of the interposer and is spaced apart from the first memory package in a second direction that is parallel to the upper surface of the substrate. A first heat transfer unit is disposed on a surface of the substrate facing the first logic semiconductor chip. The first heat transfer unit is spaced apart from the first logic semiconductor chip in the first direction.