The present invention relates to a sensing structure of touch panel, which comprises a plurality of first electrode groups are located on a first side of a substrate. The bottom of each first electrode is located on the first side and extends towards a second side. A plurality of extended electrode groups are connected to the plurality of first electrode groups, respectively. The bottom of each extended electrode is located on the second side and extends towards the first side. The plurality of second electrode groups are located on the substrate. A first sub-electrode of each second electrode is interleaved with and insulated electrically from each extended electrode. The plurality of third electrode groups are located on the substrate and have a plurality of third electrodes. A first sub-electrode of the third electrode is interleaved with and insulated electrically from the second sub-electrode of the second electrode.