An electric connection box provided with a circuit structure, a casing for accommodating the circuit structure therein, a plurality of bus bar terminals disposed on a cabling path crossing the casing in a horizontal direction and electrically connecting the circuit structure and an external connecter to each other, and a terminal support portion for supporting a horizontal portion crossing the casing in the horizontal direction in the plurality of bus bar terminals from below, in which a first rib capable of contact with the horizontal portion from below are projected on a surface opposite to the horizontal portion in the terminal support portion, and a space between the first rib is a first groove portion recessed downward.