A sensor network system and method for establishing a data transmission path are is disclosed. The method for establishing a data transmission path of a sink node and the network system which includes a plurality of nodes including the sink node, includes a) requesting nodes on a previously established data transmission path to give their adjacent node information, b) receiving the adjacent node information, c) retrieving adjacent nodes as the sink node moves, and d) reestablishing the data transmission path through the result of retrieval and the adjacent node information. Since the data transmission path is reestablished without flooding, it is possible to reduce energy of the nodes. Also, the method for establishing a data transmission path can be applied to any routing protocols without additional conditions.