The invention relates to an arc extinguishing and human body protection system of a rapid switch. The arc extinguishing and human body protection system is characterized by comprising an instation line selection arc extinguishing device, wherein the instation line selection arc extinguishing device is connected with an outer-station arc extinguishing device, a primary sub-station line selection device and a secondary sub-station line selection device through a communication center module and comprises a first controller, the first controller is connected with a bus through a voltage acquisition module so as to acquire a bus three-phase voltage and a bus zero-sequence voltage, the first controller is also connected with each outgoing line of a substation through a current acquisition module so as to acquire a zero-sequence current of each line wire, the instation line selection arc extinguishing device also comprises a first split phase rapid switch. An initial end and a tail end of a grounding point happened with a fault are connected with the ground by the phase split rapid switch, a fault grounding current is transferred within 10 milliseconds, a fault grounding voltage is limited under 36V, and the effects of arc extinguishing and human body protection are effectively achieved.