A CMOS image sensor that is capable of substantially completely intercepting unnecessary light incident from the outside and preventing the occurrence of a hot pixel phenomenon and a method of fabricating the same are disclosed. A CMOS image sensor includes an epitaxial layer having a plurality of photodiodes. The epitaxial layer may be formed over a main pixel region and a dummy pixel region, which may be defined on a semiconductor substrate. A device passivation layer may be formed by depositing and planarizing oxide over the epitaxial layer. A silicon oxide layer may be formed by depositing and planarizing silicon oxide over the device passivation layer. The silicon oxide layer may have a concavo-convex type oxide pattern over the main pixel region and a planar oxide pattern over the dummy pixel region. A plurality of dark matrix elements may be formed by sequentially stacking a dual layer and a metal layer over the silicon oxide layer. A planarization process may be performed until the concavo-convex type oxide pattern is exposed. Micro lenses may be formed such that the micro lenses are aligned with photodiodes which will be formed at the main pixel region and the dummy pixel region.