A direct-mode communication system comprises a first client direct-mode communication apparatus and a backhaul network. The first client direct-mode communication apparatus transmits a register signal to the backhaul network to register with the backhaul network. After the first client direct-mode communication apparatus is registered, the backhaul network determines a location relationship between the first client direct-mode communication apparatus and a second client direct-mode communication apparatus, and transmits a wi-fi connection signal to the first client direct-mode communication apparatus according to the location relationship. The first client direct-mode communication apparatus creates a wi-fi direct-mode communication connection with the second client direct-mode communication apparatus according to the wi-fi connection signal.