This invention provides a drive system of a display device preventing an uneven display caused by output current values of current conversion circuits. A drive system of a display device of the invention has a plurality of pixels disposed in a matrix of m rows and n columns and having current drive elements, n pieces of current conversion circuits converting digital display signals inputted from outside into analog signals corresponding to the digital display signals, a first selector circuit selectively supplying the digital display signals to the n pieces of the current conversion circuits, and a second selector circuit selectively supplying current outputs of n pieces of the current conversion circuits to pixel groups divided in columns.