Administrative Law Judges(ALJs) preside over an agency hearings with fairness and impartiality. According to the fair and impartial hearings, ALJs make an initial decision that would become the decision of the agency without further proceedings unless there is an appeal to, or review on motion of, the agency within time provided by rule. Therefore, ALJs play an important role in protecting the interests of complainants by regulating the processes of the hearings. In order to assure the role of ALJs mentioned above, the independence of ALJs from the agency and the separation of functions are insured under the enabling acts and the Federal Administrative Procedure Act. We also have presiding employees to regulate the hearings in our Administrative Procedure Act like ALJs. However, the independence of presiding employees from the agency is far less weaker than that of ALJs. In addition, presiding employees have no power to make an initial decision and are not responsible for the malpractice of the hearings like ALJs. Based on these grounds, I describe the ALJs in general(definition, appointment and sanction, quality standard to be appointed, and current situation of ALJs would be included), the role of ALJs(Federal Administrative Procedure Act, Model Code of Judicial Conduct and two resolutions of ABA would be explored) and the separation of functions(attitude of government - legislative, executive, judicial branch - would be examined) in order in this article. At the conclusion, I suggest several methods(e.g., to amend our Administrative Procedure Act § 28 ①, to insert rule of necessity into our Administrative Procedure Act § 35-2, to enact agencys' own rules for their presiding employees, and to adopt an appeal system or/and review on motion of the agency on the malpractice of the presiding employees, etc.) to improve the independence, role and responsibility of presiding employees by comparing those of ALJs.