A communication control system between parallel computers performs a broadcast communication in a network between parallel computer nodes. The communication control system includes a destination detecting unit for detecting the destination information designating the scope of the destination nodes from the data; a between-node distance processing unit for obtaining the distance between the particular computer node and the destination computer node, based on the destination information; and a destination judgment unit for judging whether the data should be obtained by the self node or whether the data should be further transmitted to the other node and for determining the direction of the transmission, based on the distance information.