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It is found the seepage at wall canal at downstream foothill in Selorejo dam. It is indication there is the water leakage from dam. To get better understanding the path of leakage water, some locations of dam have been scanned using 90 MHz GPR (Ground Penetrating Radar). The location of scanned have been done at three locations, i.e. at (1) the top, (2) two third and (3) the downstream foothill dam using profiling and common midpoint technique. At first all of location are scanned using profiling technique, if at some location the structure of soil doesn-t look clearly, the common midpoint technique is using. The methods of analysis are gain profile, bandpass filter, and average subtraction to see the radargram clearly and hodograph to show the structure of soil from radargram scanned by common midpoint technique. At the top of dam the pattern is heavily attenuated because the material at this location is dominated by clay. After applied using three methods processing in order to see the structure clearly, there are two location shows soil saturated by water. In this location the common midpoint is use to scan at 20 m and 44 m. From godograph processing at those locations it is found clay layer saturated by water started from between 4-6 meter depth. At the two third dam it is found two locations significantly show soil saturated by water even without processing. The one of pattern have 16 m wide and the other one is about 8 m. At downstream foothill there are scattered location having small patterns saturated by water. From above of data it concluded that there are two path of seepage started from the top dam. This path shows clearly at the two third highest dam and this path is unified along before downstream foothill location.