An electronic device and a control method thereof are provided. The electronic device includes a memory configured to include a non-secure region operating in a normal world and a secure region operating in a secure world, and a processor configured to selectively operate in one of the normal world and the secure world, check integrity of a plurality of code blocks loaded on a first area of the non-secure region while operating in the secure world, and when one of the plurality of code blocks is compromised, change a memory region corresponding to a compromised code block to a secure region, and load an original code block of the compromised code block on a second area of the non-secure region.