Musyarakah mutanaqishah is a modified contract from a musyarakah contract that is implemented in Islamic financial institutions as one of their financing products. As for one of the products that accompany it, namely refinancing and transfer of debt (take over). This paper aims to review the musyarakah mutanaqishah concept and its concept in Islamic financial institutions and examine briefly related to refinancing and take over products, these two products are products that cannot be separated from the musyarakah mutanaqishah contract whose implementation in Islamic financial institutions is currently widely used. The approach used in this paper is a normative juridical approach, then the type of research used is qualitative and the method chosen is descriptive analysis research method while the data is collected by literature study. Musyarakah mutanaqishah implemented in Islamic Financial Institutions is in accordance with sharia principles, this is supported by the existing DSN MUI fatwa and refinancing and take over products are also one of the conveniences in applying a musyarakah mutanaqishah contract.