To perform broadcast communication even when retry frequently occurs in individual communication in a communication system between a road and a vehicle, which performs the broadcast communication and the individual communication.

A data processing part 111 outputs N pieces of individual communication data 303 and M pieces of broadcast communication data 302 to a communication control part 112 when the number of pieces of individual communication data 303 is equal to or more than a predetermined upper limit number N, and outputs all the pieces of individual communication data 303 and N+M-k pieces of broadcast communication data 302 to the communication control part 112 when the number of individual communication data 303 is less than the predetermined upper limit number N (k pieces). The communication control part 112 generates a communication frame 305 including the number of broadcast communication data 302 equal to or more than a compensated number M by the broadcast communication data 302 and the individual communication data 303 output from the data processing part 111. A radio wave transmitting/receiving part 120 transmits the communication frame 305 generated by the communication control part 112 to each onboard unit by a DSRC beacon.