Apparatus and methods are provided for relay-assisted retransmission. In one novel aspect, the remote UE receives data transmission from the source entity through a direct link and retransmission from a relay UE. In one embodiment, the relay UE receives feedback indication from the remote UE, transmits the feedback to the source entity, and retransmits one or more TBs to the remote UE through a SL connection upon detecting one or assisted retransmission triggers. In one embodiment, the feedback is a joint HARQ, wherein a NACK is sent when both the relay UE and remote UE failed, and an ACK is sent when at least one of the relay UE and the remote UE succeeds. In one embodiment, the relay UE retransmits one or more successfully received TBs to the remote UE upon receiving a failure indication from the remote UE or receiving retransmission indication from the source entity.