A display apparatus includes; a display panel which displays an image in response to a gate voltage and a data voltage, a panel driver which receives a control signal, and which supplies the gate voltage and the data voltage to the display panel according to the control signal, a backlight which supplies a light to the display panel, an inverter which receives a backlight dimming signal, and which controls a brightness of a light emitted from the backlight according to the backlight dimming signal, and a timing controller which receives a synchronization signal, determines a frame frequency of the display panel according to the synchronization signal, outputs the control signal, and modulates the synchronization signal based on a ratio of a predetermined backlight dimming frequency to the frame frequency, and which outputs the backlight dimming signal according to the modulated synchronization signal.