The present invention is to provide an electric connection box, which can easily attach electric components to an attachment portion of box body. The electric connection box includes a box body having the attachment portion attaching the relay on an upper surface of the box body, and a relay fixed on the box body. The attachment portion includes a tube, a plurality of openings and a plurality of holding portions arranged in the opening. The tube inserts the relay into an inside thereof, and stands from the upper surface. The opening passes through the tube 5, and is arranged with a space along a circumferential direction of the tube. The holding portion presses the relay toward the inside of the tube, and holds the relay to the tube. The holding portion includes an arm and a protrusion projecting toward the inside of the tube.