Musyarakah transactions occur because of a common interest to cooperate or partner in a business that is based on mutual need, mutual trust. Musyarakah requires participation in joint funding and a division of roles in running a business, there are activities to pool capital for a business with a presentation for the agreed results. Sharia guarantees are an important part of Islamic banking financing, although there are no legal rules that require collateral in musyarakah financing, the fact is that banks always require a guarantee. The method used in this research is the normative method, by collecting legal materials in the form of regulations, journals and reference books related to the research topic. The law materials analysis used qualitative descriptive. The nonregulation of guarantees in the Sharia Banking Law creates a legal vacuum, that make bank obliges to customers provide guarantees in musyarakahfinancing. This needs special attention, because Islamic banks do not carry out sharia principles, namely on the one hand Islamic banks apply sharia financing, but on the other hand they still use a conventional guarantee system.