An image recording system, an image recorder and a data accessing method are provided. Some of memory blocks of a flash memory are set as first blocks, and the other memory blocks are set as second blocks. When a target image file received from a capturing unit of an image reorder is being written into the first blocks, a control unit of the flash memory detects whether the first block into which a processing unit of the image recorder tries to write a piece of data of the target image file is faulty. When the first block is faulty, the control unit selects normal one of the second blocks and then writes the piece of the data of the target image file into the selected second block instead of the first block.