The present invention discloses a multi-user communication scheduling system based on a full duplex relay cache and a multi-user communication scheduling method based on a full duplex relay cache. The system comprises multiple users with the need of sending information and multiple users with the need of receiving information, the information transmission between the two kinds of users is realized through a single full duplex relay with a caching function, thus the communication among multiple users is effectively assisted by the full duplex relay, and the system throughput is improved. Multiple pairs of users in communication work in a half duplex mode, through sending the sending information to the full duplex relay to be received and caching the information according to a certain algorithm, the relay forwards the information in the cache according to the result of channel measurement and a given scheduling algorithm and receives and forwards information initialization state information for a next time slot, the above steps are repeated in each time slot, thus the high efficiency operation of a multiple-user communication scheduling system based on the full duplex relay cache is ensured, and the maximization of throughput is realized.