That is the fact that conflicts occuring among teachers and among teachers-school administrators are inevitable at schools. It is very important for educational institutions managing the conflicts with the most effective ways and bringing effective solutions to conflicts for being productive. In this study, teachers' perceptions related effectiveness levels of conflict management methods used by school administrators have searched out and these perceptions have examined in terms of the number of teachers at schools and school type. The levels of effectiveness of the methods used at conflicts between teachers and teachers-school managers have revealed and compared with each other. The study has performed with 255 teachers who work at secondary schools in province of Usak. Rahim Organizational Conflict Inventory has been adapted to Turkish by Gumuseli (1994) and has used. As a result, it has found that the levels of the effectiveness of methods used in conflicts between teachers and school managers-teachers differs from each other and both the number of teachers at schools and school types have changed the teachers' perceptions.