Semiconductor package and semiconductor device including the same

A semiconductor package and a semiconductor device including the same. The semiconductor package includes: a package substrate; a plurality of connection elements that are disposed on the package substrate; and a semiconductor chip that includes at least one optical input/output element that transmits/receives an optical signal to/from the outside at an optical input/output angle with respect to a direction perpendicular to a bottom surface of the package substrate, and is electrically connected to the package substrate through the plurality of connection elements.