A two-component developer includes: a toner; a carrier having a surface energy of from about 23 dyne/cm to about 37 dyne/cm; and an external additive having a shape factor SF1 of from about 130 to about 150 and a number-average particle diameter of from about 80 nm to about 1 μm; and an existence ratio A of the external additive on a surface of the toner and an existence ratio B of the external additive on a surface of the carrier satisfying the relationship of the following Expression 1: 0.04≦B/A≦0.4.