A pixel data decompression method for decompressing a frame is provided. The method includes: loading memory storage addresses corresponding to to-be-decompressed blocks; reading and decompressing a pixel line of a current block according to a memory storage address of the current block; updating the memory storage address of the current block according to a decompression result; reading a memory storage address of a next block if decompression of a pixel line of the frame is not completed; and repeating the above steps until decompression of the frame is completed.