A CMOS image sensor and fabricating method thereof can enhance the quality of the image sensor by preventing unnecessary diffused reflection of light by providing an opaque filter layer next to a microlens. The CMOS image sensor includes a photodiode, an insulating interlayer, a metal line, a device protecting layer, a microlens on the device protecting layer and overlapped with the photodiode, and an opaque layer pattern on the device protecting layer next to the microlens.