This study aims to understand the contribution of internal audit reengineering to itsrneffectiveness in Ethiopian public enterprises. The study adopted a case study design andrnresearch questions were tested using an organization that went through internal auditrnreengineering. The questionnaire data were analyzed using descriptive statistics and datarnfrom interview and documentary review were interpreting qualitatively. The result showsrnthat internal audit reengineering basically change organizational setting and has lowrninfluence on internal audit quality and auditee attribute and there is no influence onrnmanagement support. Since the effectiveness of internal audit function is mainlyrninfluenced by management support and internal audit quality (Mihret and Yismaw,rn2007), internal audit reengineering has low contribution to the effectiveness of thernfunction