Achieving sustainable and credible reporting is not possible without relying on capable human capital. Investment in human resources includes the costs and efforts that an organization makes to recruit, train, develop, retain, and empower employees. These investments will be effective when they lead to efficiency in human resource performance and show themselves in the organization's qualitative outputs, including sustainability reporting. The statistical population of the study consists of all companies listed on the Tehran Stock Exchange during the six-year period from 1397 to 1402. Using the systematic exclusion sampling method, 136 companies were selected, which include a total of 816 company-year observations. From the perspective of the purpose, this research is classified as applied research and is classified as a descriptive-post-event study in terms of data collection method. To test the hypotheses, multivariate regression models using EViews version 10 software and panel data method (fixed effects and mixed model) were used. The results obtained show that the efficiency of investment in human resources has a significant and direct effect on sustainability reporting.