Traffic between logic LSIs and memory is increasing year by year and there is demand for increase of capacity of communication between them and reduction of power consumption in the communication. Communication distances between LSIs can be reduced by stacking the LSIs. However, in a simple stack of logic LSIs and memory LSIs, it is difficult to ensure heat dissipation to cope with increasing heat densities and ensure transmission characteristics for fast communication with the outside of the stacked package. Also required is a connection topology that improves the performance of communication among the stacked LSIs while ensuring the versatility of the LSIs. An external-communication LSI, a memory LSI, and a logic LSI are stacked in this order in a semiconductor package and are interconnected by through silicon vias. Output terminals of multiple stacked LSIs are connected to an input terminal of a through silicon via of the stacked memory LSI and input terminals of multiple stacked LSIs are connected to an output terminal of a through silicon via of the stacked memory LSI, thereby directly connecting both of the external-communication LSI and the logic LSI to a wiring line of the memory LSI.