The present invention relates to an ink cartridge. The ink cartridge comprises: a space for storing ink; an ink cartridge module having a pair of heads arranged in an offset manner such that a print width is extended; and a flexible printed circuit board connected to the ink cartridge module on a circuit configuration, wherein the ink cartridge module has a cross sectional shape in which two rectangular shapes having long sides and short sides respectively come in close contact with each other such that the long sides of the two rectangular shapes overlap in part, and thus can configure an array in the direction of either the long side or the short side. The ink cartridge according to the present invention can implement various sizes of print widths and various colors by arranging one or more ink cartridge modules adjacent to each other.