This paper examines the moderating role of Islamic corporate governance on the link between sustainable business practices and the firm's financial performance. A post-crisis period sustainability data for the decade of 2008-2017 was collected by the study. For data collection, this study used the weighted contentmethod. The Generalized Method of Moments (GMM) statistical test was used for empirical testing. The results of the study found that the link between sustainable business practices with the firm's financial performance measured from the shareholders' and the management's perspective is positive, while the subjected link measured from the market perspective was found to be insignificant. This implies that the market stakeholders of the Islamic banks are reluctant for their bank's spending on sustainable business practices. Interestingly, the insignificant link between sustainable business practices and market performance became significant with the moderating role of Shariah governance and managerial ownership. It shows that the moderating role of Shariah governance and managerial ownership is giving confidence to market stakeholders of Islamic banks for receiving a higher financial return through sustainable business practices initiatives. These results may provide insights for several policymakers of the Islamic banking industry about integrating vital sustainability practices in their business models and about the balanced moderating role of Islamic corporate governance in the link between sustainable business practice and the firm's financial performance. It provides a roadmap to the Islamic banking industry for effcient management of sustainability practices from an Islamic perspective and subsequently improvement of financial performance through it. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.