The disclosure provides a display driving device and an operation method thereof. The display driving device includes a timing controller circuit and a driving circuit. The timing controller circuit performs oblique filter processing on an original image frame to generate a processed image frame. The driving circuit is coupled to the timing controller circuit to receive the processed image frame. The driving circuit drives a display panel module according to the processed image frame. The display panel module includes a tilt lenticular lens layer having a first tilt angle. A second tilt angle of a filter mask of the oblique filter processing corresponds to the first tilt angle.