The purpose of the study was to explore instructors' knowledge, attitude and practice of differentiated instruction in the case of the College of Education and Behavioral Sciences of Bahir Dar University, Ethiopia. The study employed a qualitative research approach with case study design. The participants were the dean, department heads and instructors of the College of Education and Behavioral Sciences, Bahir Dar University. They were purposively selected on the basis of teaching experience and experience outside Ethiopia. Interview and FGD were used to collect data in this study. The data received were analyzed and interpreted through narration using data-driven categories formed within the scope of the three themes, i.e., instructors' knowledge, attitude and practice of DI. The results of the analysis showed that instructors had a positive attitude towards DI. But, they showed a moderate level of knowledge of DI and it was not properly practiced yet as expected for a number of reasons disclosed in the report. It was then concluded that the prevailing practice of DI was poor. In addition to this, the trend of using the lecture method and assessing students based on paper and pencil tests were emphasized at the College. To overcome this, it was suggested that the current mode of teaching which focused on the traditional lecture method should be minimized and complemented with the implementation of other indirect instructional strategies. It was further noted that the traditional paper-pencil assessments should be either supplemented or complemented with other authentic assessment techniques like portfolio evaluation, performance and product assessments.