The purpose of this research is to investigate the relationship between socio economicrnmarginalization and students’ academic achievement, the case of Manjo students in kefarnzone. (South Western Ethiopia) In this study, students from Manjo cultural group and thernmainstream Kefa, teachers and school directors, education experts, community leaders andrncoordinators of Nongovernmental organizations have participated. Student roaster is anotherrnsource of data for the study. The methods used in this study is ethnographic. Quantitative datarnis also used only where it is necessary. Socio economic Scale, interview, and documentrnanalysis were the instruments used for data collection. The findings of the study indicatedrnthat Manjo families have low socio economic status the bi-variate analysis has indicated thatrnManjo students’ low academic achievement is strongly correlated with their socio economicrnmarginalization. According to the findings, Manjo students with bright mined are atrndisappointment because of social exclusion and economic marginalization. As a result, theirrnacademic achievement in all levels of schooling is by far behind Non-Manjo students.rnParent’s educational background, occupation of parents, type of house, monthly per capitarnincome, study hour and family support are the major factors influencing Manjo students’rnacademic achievement. The recommendation includes Economic Empowerment of Manjorncultural group, Educating and mobilizing the society against discriminatory attitudes andrnpractices, encouraging the participation of Manjo in social, economic and political life, andrnproviding training for teachers, principals and Parent-Teacher Associations (PTA) on how tornhandle students with diverse cultural background etcrnKeywords: Socio economic, marginalization, achievement, Inclusion