This invention provides an aircraft electric generation system, which can achieve significantly increased capacity of electric generation, while adequately suppressing unwanted increase of a front face area of an aircraft engine as well as successfully dealing with considerably large changes of an engine spool speed. This electric generation system is driven by the engine and includes: a continuously variable transmission (CVT) connected with a rotation shaft of the engine; an electric generator located above the CVT and driven by an output of the CVT; and a lubricating oil pump unit located below the CVT and also driven by the output of the CVT.