A time controller with power-saving function is utilized for selecting to drive a display with progressive or interlace scan method based on if two continuous frames are dynamic. The time controller comprises an interlace scan control module, a progressive scan control module, a motion detecting circuit, a scan selecting circuit, and a data selecting circuit. The interlace scan and the progressive scan control modules are utilized for generating control signals of interlace scan and progressive scan according to a video signal, respectively. The motion detecting circuit select the control signals of interlace scan or progressive scan based on if the two continuous frames are dynamic, so as to drive the display. In this way, consumed power of the display is saved and a saw-tooth effect on the video frame is avoided.