Abstract: As the development of underwater network systems,the distributed location techniques of underwater mov-able nodes receive much concern.A location algorithm for distributed underwater movable nodes,characterized by self-organization,tolerable node failures and the range of error,low complexity and low communication burden,is pro-posed in this paper.The algorithm utilizes adaptive weighting,and circulating composite triangulation method to improve the location accuracy.The paper simulates the location accuracy of this algorithm based on TOA ranging method,analyzes the influence of the number of reference nodes on location error,and compares with trilateration location algorithm.The results of simulation show its accuracy and robustness with respect to range measurement error and node failures,and low density of reference node.