The government employees, as civil servants for the entire nationals, have their natural obligations to observe the nation's laws and regulations and to perform duties sincerely and uprightly. The article 3 of Police Law states that the duty of police is to maintain public peace and order in the society such as protecting the lives of citizens, body, property, preventing, suppressing, and investigating crime cases, collecting information on public security, regulating traffic and so on. Also, the article 2 of Act on the Performance of Duties by Police Officers endows police officers with a wide range of authority and duty to maintain public peace and order in the society such preventing, suppressing and investigating crime cases, watching, patrolling, and engaging in counterespionage operations, collecting information on public security and documenting and distributing it, controlling traffic, stopping harm, and so on. As shown in the both laws, the authority and power of police are exercised generally on individual citizens. Because of inherent problems of the police disciplinary system in Korea, police officers has deep distrust in disciplinary system and demoralization among them. So it is necessary to present reform measures to remedy these problems. Following this study, we complied with the general principle of administrative law and theoretical argument about the police disciplinary system (proportionality, Rule of equality). We considered specific fairness for the police disciplinary action through the Rule of law.