The study was setout to assess the magnitude of dropout of primary schools in WestrnHararge zone and factors affecting it. In order to achieve this purpose, basic questionrnwere raised that intended to address the magnitude of dropout by grade level and sex andrnfactors behind dropout of the system. Descriptive survey method was employed in thisrnstudy. Moreover, both probability and non-probability sampling technique were used.rnAccordingly, 7 woredas and one(1) town administration were selected from 14 woredarnand two town administrations found in the zone using simple random sampling. From therntotal of 82 complete primary schools found in the sample woredas, 30 complete primaryrnschools were again randomly selected and included in the study. Principals, teachers,rnstudent (dropout), PTAs, zone and district supervision work process owners were used asrnthe primary source of data. Questionnaire, semi-structured interview and FGD guidesrnwere used as the means of data gathering tools. Moreover, document analysis wasrnintensively made to compute the magnitude (trend) of dropout by grade level and sex ofrnthe students' population. Before administrating the questionnaire, pilot test wasrnconducted in two primary schools for validity and reliability of the items. After data wererngathered, analysis was made using tables, frequencies, percentage, mean, weighted meanrnand spearman's rank correlation coefficient. The data revealed that the rate of dropout inrnprimary schools of the study area is 12.9% in 2006107, 14.8%,2007108. 16.4%, 2008109rnhigh and its trend shows a tendency of increasing except 2009110. The data furtherrnindicate that the problem is more serious among boys than girls. Low quality teaching,rnlack of school facilities, large class size, irrelevance curriculum, long home-schoolrndistance, poor school community relation, shortage of qualified teachers, and lack ofrntraining for school managers were the cause for dropout of student. Above all, inabilityrnto afford both direct and indirect costs of education, demand for child labor, lack ofrnmaterial and financial support, early marriage (Teenage pregnancy) and lack of familyrnawareness were found to be the major impediments of dropout. Poor academicrnperformance of students, low future success expectation and repeated absenteeism werernalso the other student elated problems that causes student to dropout. To alleviate thesernproblems, recruiting more teachers, improving quality of education in general,rndiversifYing mode of delivery, creating open dialogue with community on sustainablernbasis, launching various support mechanism for economically poor students. buildingrnboarding schools, making curriculum relevant, earlier identification of potential dropout,rncreating job opportunities, and conducting further multivariate and longitudinal researchrnon the issue were suggested