Abstract: The structure characters of weighted complex networks are analysed.The effect of the edge-weight on estimation of node importance is calculated.A new definition of weighted node importance is proposed,and an improved node contraction method in weighted networks is given based on the evaluation criterion,i.e.the most important node is the one whose contraction results are the largest increase of the weighted networks agglomeration.The time complexity of this algorithm is O(n³),and the improved evaluation method can help exactly to find some critical nodes in complex networks.Final experiments verify the efficiency and feasibility of the proposed method.