The main purpose of the study was to assess on the challenges and opportunities to use ‘Tsamaako’ as a medium of instruction in the primary school in Bena Tsemay wereda, south omo zone. The study was employed survey research design. The researchers have used probability and non-probability sampling techniques for students, teachers, parents, school directors and woreda education experts to select them as respondents for the study. Specifically, simple random sampling technique was used to select students and teachers, and purposive sampling technique was used to select parents, school directors and woreda education experts as respondents. The total sample size is one hundred twenty eight (128) respondents that incorporate: students, teachers, parents, school directors and woreda education experts. The study used three types of data collection instruments: questionnaire and interview and FGD. The procedure of data collection was performed in the following steps: questionnaire was conducted at first stage and followed by interview and FGD for the target participants. After the data has been collected through different tools, it was analyzed qualitatively and quantitatively. The study result revealed that lack of understanding, absence of a clear policy that obliged the use of mother tongue education and the hegemonic position of Amharic language hinders the use of Tsamaako as a medium of instruction. In so doing, parents disregard the role of mother tongue education in favor of second language medium. The study recommended that parents should be encouraged to choose their own language for their children and others should also appreciate their choices. All stakeholders and educational practitioners should pay attention to the promotion of the language. Zonal and Woreda education offices should prepare and deliver enough textbooks and other educational materials to schools in Bena Tsemay woreda. Also highly trained and pedagogically equipped teachers should participate into the teaching learning process in order to correct the misconceptions held towards mother tongue instruction. Furthermore, preparation of well-developed dictionary and vocabularies, and general reading materials are worth enough to use Tsamaako as a medium of instruction.