Disclosed are an image data reading method and apparatus, an electronic device, and a readable storage medium, relating to the technical field of LED image display. The image data reading method includes: storing image data in each row of image blocks into a number of v storage blocks, where each of the v storage blocks stores a number of h rows, each row of data including image data stored at a same position of each group in a same row of every image block; and sequentially outputting from each of the v storage blocks by: sequentially reading each row of the image data in a vertical order, and simultaneously outputting the image data stored at the same position.