This study aims at putting forth the reasons preventing teachers from acting ethically, acting within the framework of ethical principles and having an ethical tendency. This study featuring a qualitative research model taking as a basis the case study approach followed a path of selecting people that can be a rich source of information for research instead of a random sampling to represent the universe. In this research where snowball sampling method is used datas have been obtained through negotiations with seven teachers on duty in Sinop city center. According to the results of the research, reasons preventing teachers from ethical behavior, acting within the framework of ethical principles were categorized under headings of "bureaucratic framework", "attitude of administrators", "corporate", "economic", "personal" and "occupational incompetence". [This study was submitted as an oral presentation in the 22nd National Congress on Educational Sciences held in Eskisehir Osmangazi University on 5-7 September 2013.]