The main purpose of this study was to assess the level of implementation of active learning and identify the major challenges that affect its proper implementation in the Government Secondary Schools of West Wollega Zone, Oromia National Regional State. In order to achieve this purpose, three basic research questions were set. Descriptive survey design and both quantitative and qualitative methods were employed in the study. The study was conducted in fourteen secondary schools selected from a total of 70 secondary schools using simple random sampling technique. Teachers and students were selected by stratified sampling technique while school principals and supervisors were selected by availability sampling technique. To gather data, questionnaires, interviews, observation, focus group discussion and document analysis were employed. Quantitative data were analyzed using descriptive statistical tools while qualitative data were analyzed through the use of summaries and themes. Outcomes of the study suggested that the level of implementation of active learning methodology was low as classes were more of teacher-dominated. The most dominant methods of teaching employed were lecture and direct instruction. The finding indicated that the factors that challenge the implementation of active learning were mainly administrative and curriculum related factors, rather than scarcity of material and financial resource. On the bases of the outcomes of the study, it was concluded that active learning methodology is not effectively employed to improve student learning outcomes due to in school factors. Based on the conclusions, it was recommended that, principals and supervisors should inspire and train teachers on the use of active learning method and they should change learning culture from focused on teaching to focus on learning.rnKEY WORDS: Practice of Active Learning methods, teaching method, student-centered teaching, teacher-centered teaching.