When intelligence agencies are undertaking any forms of intelligence activities, there may be lack of the definiteness of regulations, legality or human rights violations while performing the relative intelligence activities. The intelligence activities cannot get rid of such questions and dilemmas even in the democratic and legitimate society nowadays. The study aimed to discuss the possible moral issues of intelligence activities, which divided into 4 aspects such as "intelligence collection", "intelligence analysis", "counterintelligence" and "covert action", and proposed 6 methods to improve such as establishing a new intelligence perspective, the proper disclosure of intelligence activities, legalizing of intelligence activities, regulating the interaction of intelligence and policies, establishing of intelligence oversight system and achieving the balance between national security and human rights. The conclusions are provided to the intelligence agency for performing the intelligence activity as a reference.