On the Polish financial market leasing belongs, besides credit, to the most popular and used external finance sources. It isn’t now situation for credit, which belonged to the classical external finance sources for many years ago. However leasing has been obtaining its position during the last ten years. Recently some important regulations concerning leasing were arranged in Poland and it would let leasing to develop further. With its development a new type of risk has appeared, i.e. a leasing risk. This article refers to the mortgage as the way to secure the leasing receivables of a leasing company. It is the similiar situation as in the case of other finance companies, for example bank and because of that this article has in the m...