The aim of this study is to present a model of factors affecting investment inefficiency in conditions of economic policy uncertainty in the Iranian economic environment. The method of this study was qualitative and data were collected through semi-structured interviews with 17 experts in the field of investment. In this study, the text of the initial interviews was studied according to the objectives of the study. In order to analyze the data, the six-way theme analysis method using MAXQDA software was used. The results showed that the results of this study showed that institutional and structural factors including weak internal controls, administrative corruption and institutional weakness, quality of financial reporting and macroeconomic factors including exchange rate fluctuations and inflation, sudden changes in economic policies and financing constraints. Behavioral and managerial factors including conservative behavior of managers, conflict of interest and agency costs, inefficiency of financial markets including low liquidity, unexpected fluctuations, and price distortions lead to investment inefficiency in conditions of economic policy uncertainty. Finally, quantitative analysis of the model using AMOS software and structural equation modeling showed the significance of all the model constructs and confirmed it