A structure of embedded memory unit with loader comprises a main memory area and an information area as a part of the main memory area. A plurality of loader-program parts is dispersedly stored in different addresses of the main memory area, wherein the loader-program parts are combined to form a complete loader. A loader mapping area is used to store the loader-program during the boot stage. When the boot sequence starts, the original information stored in the loader mapping area is temporarily backup to a temporary space; and the released space is used to store the loader-program. After the boot sequence is completed, the original information is moved back to the original location.