As DV-Hop algorithm estimates distance by distance vector exchanging, positioning process is vulnerable to devastate wormhole attacking. An improved DV-Hop algorithm (AWADV-Hop) which resists wormhole attack is proposed, based on the original algorithm in this paper. To solve the problem that hops and the average distance per hop is the most vulnerable to wormhole attack in DV-Hop. This paper first fixes hop value by detecting the wormhole attack. Then, according to error comparison of the average distance per hop of anchor node and the average distance per hop of the whole network, locate permission of anchor nodes are re-decided. Average distance per hop of anchor nodes with positioning permissions is weighted to be the ultimate per hop distance of unknown node. Finally, simulated by MATLAB and simulation results show that this algorithm can effectively resist wormhole attack and improve the positioning accuracy.