A data processing apparatus which enables power saving in a NoC structure that is not limited in routing. The data processing apparatus has a plurality of data processing modules, which performs data processing, and a plurality of routers, which relays data transmission between the plurality of data processing modules. It is determined whether or not data is stored in a connected data processing module among the plurality of data processing modules, and according to a result of the determination, a power saving instruction or a wakeup interrupt is issued for the connected data processing module.