The aim of this study is to determine whether math teachers have an idea about the open course materials and to get their opinions about the use of open course materials. The study employs a qualitative research approach. The research is carried out on 12 math teachers with professional experience working at all two high schools in the Eastern Anatolia Region in Turkey. In the research, Open Course Materials Interview Form (OCMIF) developed by the researchers was applied as a data collection tool. The content analysis method is used for data analysis. According to the results, it was seen that the teachers had information about the open course materials. Teachers also expressed the opinion that those not insufficient and uncontrolled for such sharing would be unhelpful. In addition, the teachers stated that there are some situations in which open lesson materials are not used in our country. In addition, pre-course preparation and post-course evaluation, the smart board for documents and topics related to the use of video, presentation, animation, such as to benefit from the activities were used.