Background: Today, one of the most important concerns in the pharmaceutical industry is achieving sustainability, and the pharmaceutical industry is recognized as a leading sector in corporate sustainability reporting. The purpose of this study was to identify, extract, prioritize and analyze the social factors and corporate characteristics which are effective in the sustainability reporting of Iranian pharmaceutical companies. Methods: This was a cross-sectional study conducted in autumm 2020. The expertise and availability principles were used for sampling, and the snowball sampling method was used for sample selection. In order to identify and extract effective social factors and corporate characteristics, the method of content analysis and the study's review of literature have been used. The survey was conducted on 40 experts in the field of research using a researcher-made questionnaire. In order to purify the effective factors, Delphi method and the Analytic Network Process method based on Fuzzy DEMATEL were used. Results: In terms of a strong interaction, the criterion for university-industry collaborations came first, and the criterion for sustainable innovation and cooperation with other companies came next. In this study, profitability, research and development intensity and the financial leverage were considered to be weak causal variables and sustainability reporting, an effect variable. Conclusion: The results showed that Iranian pharmaceutical companies, in order to achieve the goals of sustainable development, should emphasize the continuous and regular presentation of annual sustainability reporting, and in this regard, key factors such as the criteria of university-industry collaborations, sustainable innovation and cooperation with other companies should be considered critical priorities.