Environmental sustainability represents nowadays a significant factor for business sector. Firms carry out many initiatives to develop environmental practices. Investors increasingly consider environmental discloser by firms and integrate this disclosure into the investment decision-making process. Using a database of Saudi listed firms, this study adds to the literature by examining the relationship between the environmental sustainability disclosure and stock return and whether this relationship is moderated by the financial constraints. We find that the environmental sustainability disclosure has significant and negative impact on stock return, indicating that investors do not consider environmental disclosure when valuing the stocks. Furthermore, our results propose that the negative impact of environmental disclosure on stock return is more evident in firms with financial constraints. This study provides managerial implications for regulatory authorities, firms and investors. The environmental practices can be value relevant. However, these practices need to be efficiently integrated into stock valuation.