In Malaysia, Islamic affairs institutions play an essential role in ensuring the development and progress of Islamic affairs. However, in most cases, the institutions in charge of Islamic affairs face many challenges in maintaining the purity of the Islamic faith and teachings in this country. In response to this, it is imperative to understand the factors that can enhance the sustainability of Islamic affairs. Therefore, the objective of this paper is to explore the factors affecting the sustainability of Islamic affairs in Malaysia. By integrating Interpretive Structural Modeling (ISM) and Matrix of Cross-Impact Multiplications Applied to Classification (MICMAC), this study developed a novel model to ensure the sustainability of Islamic affairs. The findings of the model indicated that Islamic Religious Education (IRE) is the most influential factor in creating the sustainability of Islamic affairs. On the other hand, Society Well-Being (SWB) is the most dependent factor influenced by all other factors considered in this study. Accordingly, it is postulated that the identification of significant factors and the utilization of the proposed model could guide various stakeholder groups, such as policymakers, policy executors, and Islamic affairs practitioners, to achieve long-term sustainability. This model could also be adapted by Islamic institutions in other countries to formulate appropriate efforts to strengthen the development of Islamic affairs based on the critical factors of relationships. © 2024 The authors.