A comparison circuit that includes an input sampling capacitor and an image sensor including the same are provided. The comparison circuit includes an amplifier configured to receive a pixel signal and a ramp signal to perform a correlated double sampling operation, a first pixel capacitor connected to the amplifier through a first floating node and configured to transmit the pixel signal, a first ramp capacitor connected to the amplifier through a second floating node and configured to transmit the ramp signal, a second pixel capacitor connected in parallel to the first pixel capacitor, and a second ramp capacitor connected in parallel to the first ramp capacitor, wherein the second pixel capacitor is formed between the first floating node and first peripheral routing lines, and the second ramp capacitor is formed between the second floating node and second peripheral routing lines.