A packet transmitting apparatus comprises a wireless LAN base station and wireless terminals connected to the wireless LAN base station through the wireless LAN. From the wireless LAN base station to the respective wireless terminals, data packets are transmitted in a signal form of frame burst packets without an ACK and a series of header information on the respective data packets are transmitted as notification packets in a signal form of multicast packets. Data packets are individually transmitted from each wireless terminal to the wireless LAN base station by unicast using ACK. Each wireless terminal transmits to the wireless LAN base station a retransmission request to retransmit an unreceived data packet among the frame packets notified by corresponding one of the notification packets. The wireless LAN base station retransmits the packet corresponding to the retransmission request to the wireless terminal that transmits the retransmission request by unicast using ACK.