The purpose of this study was to identify the major effects of teaching staff turnover in AAiT. To this end, answers to basic questions pertaining to the major causes that contribute to teaching staff turnover in Addis Ababa Institute of Technology, the extent has the teaching staff turnover influenced the academic performance of students, to identify the steps to overcome the problems of academic staff turnover, and to identify what strategies adopted in order to reduce academic staff turnover and influences on students’ academic performance were sought. A descriptive research method of study was employed to reveal the effects of teaching staff turnover in AAiT. The sample population involved 120AAiT academic staff employees who were selected using simple random and purposive sampling techniques. In this study, both primary and secondary sources of data were used. The primary sources were the AAiT academic staff employees. Secondary sources such as books, reports prepared by AAiT were considered. As far as, data collection instruments questionnaire, document analysis and interview were adopted. The questionnaire was pilot-tested and modified. The questionnaire was distributed and completed by 120 teaching staffs of AAiT. The data gathered were analyzed using such statistical tools as percentage, mean, frequency, and standard deviation. The result of the study showed that insufficient wages was a means for teaching staff turnover. The result of the study also portrayed thatlack of career development opportunity was the means of teaching staff turnover.Moreover, teaching staff turnover highly influences instructional quality. Therefore, it is concludethata result of turn over the institute replace experienced and qualified teachers by non-experienced teachers. Here, turnover of teaching staffs deteriorates instructional quality.Hence, it was recommended that the institute leader and human resource management department revised salary scale and set other benefits such as transport allowances and house allowances by convincing the concerned bodies,Assignedline management are better trained in the art of effective supervision. And it may also require providing training and education opportunity to retained teachers.