The main purpose of this paper is survy of factors associated with reliance of external auditors on entenal adutors work , Reliance on internal auditors work has significant influence on cost saving and obtaining more services to client with the same cost. Optimal utilization of internal audit work can improve both the efficiency and the effectiveness of external audits and can enhance the value of internal audits to the client organization. The objective of this study is reorganization of factors associated with reliance of external auditors on internal auditors work from CPAs view. Methodology of this study is survey and needed data we use Pearson correlation coefficient and multiple regression. The results indicate competence, work performance, due professional and inherent risk level have significantly positive valuation with reliance of external auditors on internal auditors work.