Image sensing devices are disclosed. In an embodiment, an image sensing device includes a semiconductor substrate including a first surface and a second surface facing or opposite to the first surface, and structured to include a pixel region in which photoelectric conversion elements are formed to correspond to unit pixels and a pad region that is located outside the pixel region while having an electrode pad, a pixel isolation pattern disposed between the photoelectric conversion elements in the semiconductor substrate, and a pad isolation pattern disposed between the pixel region and the pad region in the semiconductor substrate.