The aim of the study was to assess the factors affecting the teaching learning process of physical education in Shashemene woreda secondary schools in West Arsi Zone Oromia regional state. Descriptive survey method was employed in order to answer the research questions of the study. The study was used purposive sampling techniques for PE teachers and school principals and stratified random sampling method for students to select samples from the total population. Data was collected through questionnaires, interviews and observation. The total samples size was taken from two schools and they totally were 318, which consisted of 4 Principals, 3 Physical Education teachers and 311 students. The collected data were organized, analyzed, tabulated and interpreted by using percentage and frequency. The major identified problems were lack of motivation of PE teachers, lack of teaching materials, problem of large class size, teaching methodology, insufficient instructional time and the role of school management and working condition of the school compound. The researcher recommended that the concerned bodies of education, PE teachers as well as students and school management should show unreserved effort to provide and fulfill inadequate instructional resources and facilities as well as give training for PE teachers and drawing students’ attention to the purpose are the possible solutions to overcome the challenges. Key words: - large class size, Teaching Methodology, Instructional time