a cmos image sensor and method for fabricating the same improve image characteristics by eliminating the thickness of a planarization layer . the cmos image sensor includes a semiconductor substrate ; a plurality of active devices , provided in a predetermined surface of the semiconductor substrate , for generating electrical charges according to an amount of incident light ; an insulating interlayer formed on an entire surface of the semiconductor substrate including the plurality of active devices ; a color filter layer formed on the insulating interlayer , the color filter layer comprised of red , green , and blue color filter patterns for respectively filtering light according to wavelength , the color filter patterns arranged to correspond to the plurality of active devices ; and a plurality of microlenses formed on the color filter layer , wherein the color filter layer is planarized so that each color filter pattern of the color filter layer is imparted with an equal height for receiving the plurality of microlenses .