Disclosed are an image sensor and a method for manufacturing the same. The image sensor includes readout circuitry and an inter-layer dielectric layer on a first substrate, a metal line in the inter-layer dielectric layer and electrically connected with the readout circuitry, a plurality of contact plugs on the metal line, and an image sensing device on the contact plugs. The image sensing device is electrically connected to the metal line through the plurality of contact plugs. The method for manufacturing an image sensor includes forming a readout circuitry on a first substrate, forming an inter-layer dielectric layer on the first substrate, forming a metal line in the inter-layer dielectric layer such that the metal line is electrically connected with the readout circuitry, forming a plurality of contact plugs on the metal line per unit pixel, and forming an image sensing device on the plurality of contact plugs.