Provided are a system and method for checking the security of a personal computer (PC). The system and method automatically check security to protect a PC from computer hacking, viruses, worms, Trojan horses, etc., and inform or cure a vulnerable point. The system and method automatically check and modify all the security check items so that a user who may not have professional computer knowledge can readily cope with a cyber attack, and describe the vulnerable point and the result of the cure to the user with ease. Therefore, the system and method can maintain a PC in its up-to-date state to prevent damage from a cyber attack, and minimize damage from a cyber threat against the main system and service.