An authentication method and an authentication system based on forking, and a forking authentication device are provided. The method includes: setting authentication credentials on the receiving devices and the original device respectively; a forking network element forking a calling request after receiving the calling request from the original device, and transmitting the forked calling request to the corresponding receiving devices; the forking network element receiving challenging values from a plurality of receiving devices, and forwarding a plurality of challenging values to the original device; the forking network element receiving the calling request which is retransmitted by the original device, wherein the retransmitted calling request carries relevant authentication credentials; and the forking network element forking the retransmitted calling request, and transmitting the forked calling request to the corresponding receiving devices, such that the receiving devices authenticate the original device according to the authentication credentials.