The weaknesses of ranging techniques on using RSS in indoor localization are fluctuating the RSS values. This situation will affect to the accuracy of distance measurement between anchor and target node. The accuracy in node position is not only influenced by accurate distance measurements, but also the geometric effects between anchors and targets. In this paper, we present a localization technique by using weighted geometric dilution of precision (WGDOP). We design an anchor set to estimate a target. The initial estimation was estimated by using trilateration and geometric dilution of precision (GDOP) then we implemented WGDOP as the weight for the estimation of several anchor sets offered. We evaluate the performance of WGDOP, this technique can increase the accuracy by 40% than without used weight in this system.