the aim of this research is to provide a model to identify the environmental and political factors affecting the public sector accounting conservatism. In terms of research orientations, the current study is a combination of applied and developmental studies. The statistical population includes academic and professional experts who work in the field of public sector financial reporting. The results indicate that the 19 environmental factors indicators were finally approved by the fuzzy screening technique are classified into one level using the interpretative structural method. Also, the 20 political factors indicators were finally approved by the fuzzy screening technique are classified into six levels using the interpretative structural method. Moreover, the results related to the fuzzy analytic network process showed that the index of "financial manager gender" is the most important index among the indices of environmental factors. The "cultural worthiness" index is in the second place and the "organizational environment" index is in the third place of environmental factors. The results related to the political factors showed that the index of "the government political ideology" is the most important index, and the indexes of “political competition” and “political incentives for reporting" were ranked second and third in importance, respectively. The findings of this research will be of great interest to managers, regulators, and those that engage in academic research in the nonprofit sector as they provide initial insights into the properties of accounting conservatism in this important sector of the economy.