A route information exchange method executed by a communication node (A1) determined as a management node (CH) that manages a layer of the hierarchical network structure in a Mobile Ad-hoc Network, MANET, comprising: receiving a route control message (D100h) from an adjacent communication node which is in the role of a management node (CH) ; identifying whether or not a routing domain, which is a network connection range and forming a hierarchy having a common uppermost layer communication node, to which the adjacent communication node (CH) belongs is the same routing domain of the communication node (A1) by comparing hierarchical information (AD100) included in the route control message (D100h) and hierarchical information (AD100n) held by the communication node (A1) with respect to an identifier (AD100t) indicating the common uppermost layer communication node of a hierarchical network structure and an identifier (AD100s) indicating the adjacent communication node (CH) as a transmission source communication node respectively, wherein the identifiers (AD100t, AD100s) are written in the hierarchical information (AD100) which includes identifiers of the management nodes (CH) that manage each layer of the hierarchical network structure and the transmission source communication node; advertising route information held by the communication node (A1) when the routing domain to which the adjacent communication node belongs is different from the routing domain of the communication node (A1); and performing construction of the hierarchical structure of the routing domain of the communication node (A1) by using the received route control message (D100h) when the routing domain to which the adjacent communication node (CH) belongs is equal to the routing domain of the communication node (A1). receiving a route control message (D100h) from an adjacent communication node which is in the role of a management node (CH) ; identifying whether or not a routing domain, which is a network connection range and forming a hierarchy having a common uppermost layer communication node, to which the adjacent communication node (CH) belongs is the same routing domain of the communication node (A1) by comparing hierarchical information (AD100) included in the route control message (D100h) and hierarchical information (AD100n) held by the communication node (A1) with respect to an identifier (AD100t) indicating the common uppermost layer communication node of a hierarchical network structure and an identifier (AD100s) indicating the adjacent communication node (CH) as a transmission source communication node respectively, wherein the identifiers (AD100t, AD100s) are written in the hierarchical information (AD100) which includes identifiers of the management nodes (CH) that manage each layer of the hierarchical network structure and the transmission source communication node; advertising route information held by the communication node (A1) when the routing domain to which the adjacent communication node belongs is different from the routing domain of the communication node (A1); and performing construction of the hierarchical structure of the routing domain of the communication node (A1) by using the received route control message (D100h) when the routing domain to which the adjacent communication node (CH) belongs is equal to the routing domain of the communication node (A1). <EOS>