Based on Received Signal Strength Indicator(RSSI) of Wi-Fi network, a weight-select and weighted localization algorithm is presented. It sets a range for the RSSI of each Acess Point(AP) at each reference location in Radio Map. And plus 1 to the weight value of each reference location if the RSSI of the AP scanned is in the range preset, and then calculate the estimated location of the target by using the weighted algorithm. Experimental results confirm that the proposed localization algorithm decreases the location error caused by the random noise of RSSI, and can obtain a more perfect positioning accuracy.