In the Islamic banking system, giving interest-free loans which is aimed at the improvement of the livelihood and economy of the needy strata requires sufficient financial resources. Considering the large numbers of applicants of interest-free loans coupled with the shortage of financial resources, we must begin to think towards the strengthening of the mentioned resources. On the other hand, the financial institute of endowment which pursues a goal similar to interest-free facilities', and both official and nonofficial reports give an indication of undesirability of the efficiency of endowed resources in Islamic societies (due to various reasons including different cultures and systems of administration and exploitation of endowments) can support interest-free-loan affairs. As the results of various studies in various societies show that nowadays in some Islamic societies, the highness of the efficiency of endowed resources is considered as a column of research advances and, growth of welfare and economic indices as well. on this basis, in the present study we have tried to identify certain ignored capacities such as endowment as well as investigating them in the forms of following subjects in order to both be able to prevent the loss of endowed resources, and to take a positive step towards the improvement of effectiveness of endowment and interest-free-loaning: using the sales price of endowed properties in the interval between the sale of old endowed properties and procurement of new endowed properties in interest-free-loan section, endowment of the interests of financial properties such as stocks, and nonfinancial properties for interest-free-loan purposes, endowment of monetary interests for good and interest-free-lending purposes, and exploitation of another series of endowed financial resources in interest-free-lending.