Provided are a CMOS image sensor in which microlenses are formed in a remaining space in a patterned light shielding layer to improve image sensor characteristics and to protect the microlenses during packaging, and a method of fabricating the same. The CMOS image sensor may include: a semiconductor substrate; at least one photodiode on or in the semiconductor substrate; a first insulating layer on the substrate including the photodiode(s); a plurality of metal lines on and/or in the first insulating layer; a second insulating layer on the first insulating layer including at least some of the metal lines; a patterned light shielding layer on the second insulating layer; and microlenses in a remaining space on the second insulating layer.