Provided is a security device, an electronic device, a secure boot management system, a method for generating a boot image and a method for executing a boot chain. The security device includes a key deriver configured to receive a root key and a protected boot key included in a boot image and generate a derived key according to a key protection method using the root key and the protected boot key, a key processor configured to perform verification according to the key protection method using the generated derived key to extract a boot key from the protected boot key included in the boot image, a secure booter configured to perform verification on a protected execution image included in the boot image using the extracted boot key, and a processor configured to execute a verified execution image on which the verification has been completed by the secure booter.