A driving apparatus for a display device includes a gray voltage generator that generates a plurality of gray voltage sets, each including a plurality of gray voltages having different levels, and a signal converter that includes a first selector for selecting one gray voltage set among the plurality of gray voltage sets on the basis of a first portion of an image signal and a second selector for selecting one or more gray voltages among the plurality of gray voltages belonging to the selected gray voltage set on the basis of a second portion of the image signal to output and select gray voltages with a smaller size digital-analog converter.