Abstract: Based on compiler analysis and combining handware and software,this paper put forward a protected frame- work in order to prevent attackers to read, analyse and tamper the compiled executable code when the process compiler compiles the source code. Firstly, classifying specific application requirement(data important and algorithm important)， then extracting key code block and generating marked binary code after classification, synthesizing the advantage of digi tal signature(RSA) and (AES) encryption and decryption algorithm, employing digital signature and encryption to en- crypt block marked information,finally loading it to FPGA to verify and run. The experimental analysis show that the method has good maneuverability and maintainability, can reduce the software protection costs and system implement cost, and reach the purpose of protection.

Key words: Code security, Kcy code block, Application requirement, Digital signature, FPGA