A redial system for a VoIP modem includes a subscriber line interface circuit (SLIC) for interfacing analog telephone signals from a telephone set to the VoIP modem and for generating redial signals to a public switched telephone network (PSTN), a first relay for connecting the telephone set with the PSTN or connecting the telephone set with the SLIC, a dummy load, a second relay connected between the PSTN and the dummy load for establishing or de-establishing a connection between the PSTN and the dummy load, a third relay connected between the first relay and the SLIC for establishing or de-establishing a connection between the first relay and the SLIC, and a control circuit for controlling the second and third relays to establish the connection between the PSTN and the dummy load and de-establish the connection between the first relay and the SLIC during the generation of the redial signals.