A stitching display system includes a control device and Q displays, and Q is a positive integer greater than or equal to 2. A image processing method includes: obtaining at least one frame of initial image; splitting each initial image into Q first sub-images according to a resolution of each initial image and an arrangement of the Q displays; outputting the Q first sub-images obtained by splitting each initial image respectively to the Q displays; and displaying a first sub-image obtained by the each display according to a physical resolution of the each display.