an electric connection box for connecting a plurality of sub - wire harnesses is disclosed . the electronic connection box comprises a power supply section , a plurality of sub - wire harness connection plates , a plurality of intermediate connection terminals , and a connection section . the power supply section has terminal sections . the plurality of sub - wire harness connection plates are laminated on the power supply section . each sub - wire harness connection plate has a plurality of set grooves to put electric wires of a sub - wire harness thereinto . each set groove of sub - wire harness connection plate has a plurality of through holes formed at a bottom thereof and spaced apart from each other in a longitudinal direction thereof . each intermediate connection terminal is electrically connected to an electric wire of a sub - wire harness and is set in a set groove of a sub - wire harness connection plate so that a through connection conductor connection section thereof is aligned with a through hole of the set groove . the connection section has a plurality of through connection conductors . each through connection conductor is connected to a terminal section of the power supply section after being inserted through a predetermined through hole in each of the sub - wire harness connection plates and connected to each through connection conductor connection section aligned with the predetermined through hole .