A display driving apparatus including a signal transmission interface, a timing control circuit and an image detection circuit is provided. The signal transmission interface is configured to receive video image data and output the video image data. The timing control circuit is configured to receive the video image data and drive a display panel based on the video image data. The image detection circuit determines whether the video image data is a static image and determines whether the display driving apparatus operates in a power-saving mode based on the determination result. Under the power-saving mode, the signal transmission interface masks a part of the video image data, so as not to output the masked video image data to the timing control circuit. Furthermore, a display driving method adapted for the foregoing display driving apparatus is also provided.