The present invention discloses a method for implementing multicast on a shared network, which includes receiving a multicast program request from a terminal device; updating an entry corresponding to the multicast program requested by the terminal device in a table of correspondence between multicast program information and terminal device identifiers according the multicast program request, where the table of correspondence between multicast program information and terminal device identifiers includes a plurality of relation entries, and each entry corresponds to a different multicast program and includes identifier information of terminal devices that request the multicast program; and providing the multicast program and the identifier information of terminal devices in the updated relation entry for each terminal device in the broadcast manner, where the identifier information of terminal devices is used to indicate whether each terminal device needs to receive the multicast program.