As an institution that is trusted by the public to manage zakat funds, zakat institutions have full responsibility in managing zakat funds in a transparent and accountable manner. However, in several cases, the management of zakat has not been managed professionally which subsequently this condition will lead to the shrinking of public trust towards zakat management organizations (ZMO). The Zakat Core Principles (ZCP) as the guidance of good zakat governance encourages ZMO to construct and conduct the internal audit in order to preserve transparency and accountability principles in managing zakat fund. However, the internal audit standard for ZMO has not been constructed yet which resulting to an imbalance circumstance between large zakat institutions that already have comprehensive internal audit standards and small zakat institutions that do not have an internal audit. Hence, in the absence of the national internal audit standard for ZMO, this research would like to propose the designing of internal audit standard which can be adopted by ZMO nationally. By using the Delphi method, the study has successfully constructed 3 main standards and 20 sub-standards of internal audit for ZMO