The utility model discloses a multi -functional earth connection case, a serial communication port, include: the plastic width -lock type single -layer sealed packing case comprises a casin. The admission machine constructs, and its holding is in in the box, the apron, it is used for the closing cap the box, be equipped with ground outlet and a plurality of port of being qualified for the next round of competitions on the apron, the one end of earth connection forms the earthing terminal, many the earthing terminal interconnect of earth connection passes through the ground outlet stretches out, and the other end of earth connection forms the link, and a plurality of links are respectively through a plurality of the port of being qualified for the next round of competitions stretches out, and the fastener, its with the connection can be dismantled to the link of earth connection. The utility model discloses a preparation work and round -off work can be shortened greatly in the multi -functional earth connection case simple structure operation of being convenient for, and many piece -root graftings ground wire mutual independence can automatic winding and spacing, greatly reduced staff's intensity of labour to, the staff passes through the connection condition that the pilot lamp can audio -visual each earth connection of judgement.