Abstract: Ecolocation is a localization technique based on RSSI.However,the construction of constraint table of the algorithm is not perfect.Two approaches are proposed to improve the localization performance of Ecolocation.Firstly,the data in the constraint tables are unified by RSSI values.Secondly,the comparative sources of sequence order are unified by the data of unknown nodes.The procedure of the improved algorithm is shown.Simulation results indicate that location accuracy is distinctly improved with slightly increasing of the time for improved algorithm.If the proportion of anchor nodes increases,the localization error of the improved algorithm will decrease obviously.