A shielded insertion and connection structure for a flat cable connector includes a receiving housing and a hold-down member. The receiving housing forms a receiving compartment and two side walls formed at opposite ends of the receiving compartment. The hold-down member has opposite ends that respectively form pivot structures for pivotal coupling to the side walls and rotation between an open position and a holding position. The hold-down member is made of metal and the receiving housing is at least partly made of metal to form a conduction section, which is connected to a grounding terminal. When the hold-down member is at the open position and a circuit flat cable is inserted into the receiving compartment, the hold-down member is operated to depress and hold the circuit flat cable and the hold-down member is put in electrical connection with the grounding terminal through the conduction section.