摘要：The presence of Islamic banking institutions in Indonesia, is the need for the Muslims in Indonesia, to ensure their financial transactions based on sharia. One of practice sharia agreement that took place in Islamic banking in Indonesia, namely agreements financial transactions using the mudaraba. This paper aims to examine the application of the principle of proportionality to the mudaraba agreement practices in Islamic banking in Indonesia. This study can contribute as a scientific reference for the reconstruction of the mudaraba agreement to keep the principle of proportionality in accordance with Islamic principles. To achieve the intended purpose of the study, the research method used is a normative legal research methods, with a source of primary legal materials mudarabah written agreements contained in the Islamic banking in Indonesia. Also the secondary law in the form of literature and other scientific papers which contain legal doctrine and opinion of an expert on sharia agreement, particularly on the mudaraba agreement. The results showed that the application of the principle proportionality in mudaraba agreement in Indonesian Islamic banking has not been going according to standards set by the sharia frame because in fact some of the clauses contained in mudarabah impressed provide opportunities for the shahibul maal (the Islamic banks) to disassociate ourselves from loss financial occur in the future, which is as if the financial loss was only covered by mudharib (businesses man), so that it deviates from the spirit of the principle of proportionality which should be the basis of the establishment of the nomenclature of the mudaraba agreement.
