Using optimization algorithm to solve the node localization problem has become a research focus.This paper makes deep analysis on the distance relationship between two successive localization results and designs a neighborhood function

and then proposes the greedy localization algorithm based on greedy idea.The proposed algorithm is divided into two phases.In the first phase

a set of estimated positions is generated based on the greedy iterative optimization.In the second phase

some unknown nodes will be elevated to anchor nodes

and the first phase is executed again.The second phase is repeated until there is no node that can be elevated to an anchor node.Finally

the experimental results show the proposed algorithm achieves more accurate result and take less time than the existing optimization localization algorithms.