Provided are an image sensor and a method for manufacturing the same. The image sensor comprises a semiconductor substrate, an interconnection and an interlayer dielectric, a lower electrode layer, an image sensing device, a first via hole, a barrier pattern, a second via hole, and a metal contact. The semiconductor substrate comprises a readout circuitry. The interconnection and the interlayer dielectric are formed on the semiconductor substrate. The lower electrode layer is disposed over the interlayer dielectric. The image sensing device is disposed on the lower electrode layer. The first via hole is formed through the image sensing device. The barrier pattern is formed on a sidewall of the first via hole. The second via hole is formed through the lower electrode layer and the interlayer dielectric under the first via hole. The metal contact is formed in the first and second via holes.