The present study is a quasi-experimental and applied study and has been done through different stages and with a qualitative or judgmental method. The qualitative part of the research includes interviews with experts. The statistical population of the present study consisted of experts familiar with the subject of research (university professors in the field of accounting and finance) and relevant managers and experts of auditing firms and those in charge of affairs in the auditing organization. After counting the comments, the research data were analyzed using the fuzzy Delphi method and fuzzy network analysis. Based on the results obtained from the fuzzy Delphi method, external auditing quality, legal requirements, professional standards, auditors' professional independence, professional ethics standards in auditing, auditing clients, professional staff of auditing firms, competition In the auditing market and finally the general public were the factors affecting the quality of auditing firms. The findings of the study indicated that the standards of professional ethics and legal requirements had the first and second priorities, respectively.