The main purpose of this study was to investigate English language teachers’ knowledge, attitudes and perceived classroom practices of differentiated instruction in English classrooms at some selected general secondary schools of west Gojjam zone, Ethiopia. So as to achieve this goal, a mixed research design was employed. Forty five grade nine English language teachers of Wad, Arbegnoch, Anjenie, Gelila, and Yezeleka general secondary schools were selected as participants using comprehensive sampling technique. Interview, questionnaire, and observation were utilized to gather data. The findings indicated that the English language teachers had good conception about differentiated instruction, but there was approximately no practice. The results also revealed that teachers had an adverse attitude towards differentiated instruction. Moreover, large class size, time constraint, lack of commitment and motivation due to inadequate payment, job dissatisfaction due to unmotivated learners and so were reported as deterring factors for DI implementation in EFL classrooms at schools. Based on the findings, it is possible to conclude that EFL teachers’ had a good awareness of DI, but they have lack of commitment in practicing it in the EFL classrooms. Finally, taking note of the results, recommendations were ahead.