A pixel interpolation method includes the following steps. First, multiple first macroblocks and second macroblocks are generated according to pixel data of a first real pixel row and pixel data of a second real pixel row, respectively. Next, block matching is performed on the first and second macroblocks to find a minimum block difference and a detected direction of a target pixel belonging to a first interpolated pixel row. Thereafter, the target pixel of the first interpolated pixel row is generated by way of interpolation according to the pixel data of the first and second real pixel rows and the detected direction.