An electrical junction box includes a case body having a plurality of connector portions, a power supply side circuit board accommodated in the case body and a general-purpose connector mounting unit provided in the case body and configured such that a plurality of types of connectors are selectively attached to and detached from the general-purpose connector mounting unit. The general-purpose connector mourning unit is configured such that a power supply side terminal of the plurality of types of connectors is electrically connected to a terminal connection portion of the power supply side circuit board.