As the number of non-regular employees has been increased sharply since 1997 when the financial crisis occurred, its scale in the public sector also has been increased rapidly. The portion of non-regular employees is over one third of whole wage earners nationwide now. Among those employees in the public sector, this study focuses on the school employees. The purpose of this study is to analyze problems of those school employees as they are covered by different kinds of employers; the parties to employment contracts applied by the Labor Standard Act on one hand, and the parties to collective bargaining stipulated by the Trade Union and Labor Relations Adjustment Act on the other hand. It means that the term of ‘employer’ under both the Labor Standard Act and the Trade Union and Labor Relations Adjustment Act are stipulated as the same meaning, however, as its interpretations are different under different acts, this will definitely create a lot of confusion and it is worried to destabilize legal stability. Firstly, about the employer under the Labor Standard Act, both the Labor Relations Commission and courts of justice have almost the same opinion that the superintendents of education are recognized as the parties as employers to enter into employment contracts. On the contrary about the employers for collective bargaining, school principals are considered as the parties, it’s a problem. The employment contracts should be entered into by those employers and employees who are able to determine their own employment conditions. However, the judgement that school principals are parties to collective bargaining has not been made from close considerations because the employers as the parties of collective bargaining should have the power to determine conditions of employees collectively. After studying whether or not such judgment was appropriate, the conclusion is as it follows. Because the suitable party to collective bargaining of the school sector is the superintendent of education, the counterparty for collective bargaining offered by the trade union should be the superintendent of education. Furthermore, the matters what a school principal is suitable to be the party to collective bargaining should be restricted to the matters applied to the school individually. That is the scope that a school principal is qualified to be the party to collective bargaining. This theorizing will secure stable labor-management relationships, and will keep consistency for determining as employer under the Labor Standard Act. By theorizing eligibility of employer to collective bargaining with workers in the public sector including school sectors in the future, it is expected to have opportunities to show directions of relations between the labor and management.