A packet retransmission control system includes an application processing module on which an application for executing communication processing operates, a retransmission control determination module which determines whether to execute high-speed retransmission control by a lower layer based on a predetermined rule with respect to a packet whose sending is requested by the application processing module, a packet processing branching module which allocates a packet determined to be subjected to high-speed retransmission control and a packet determined not to be subjected to high-speed retransmission control, an MAC retransmission control module which executes retransmission control of a transmission packet by a retransmission time-out shorter in time than a protocol of a transport layer with respect to a packet determined to be subjected to high-speed retransmission control, and an external output module which externally outputs a packet sent from the MAC retransmission control module or the packet processing branching module.