Example embodiments are directed to an ink discharge device that discharges uniform amounts of ink droplets from an inkjet head, and a control method thereof. Voltages applied to plural nozzles of the ink-head are changed based on different characteristics of the respective nozzles to discharge uniform amounts of ink droplets from the nozzles. Voltage increments are calculated using a fixed target color value so as to set color value dispersion and voltage increments are calculated using different target color values according to the nozzles so as to satisfy color value differences between the neighboring pixels and thus time required for a DPN process is shortened, and excessive changes of the applied voltages are prevented and thus a preparatory period required to mass-produce an LCD panel is shortened and yield of the LCD panel is increased.