Recently, paper based transactions are being replaced by digitized transactions in a rapid pace. These kinds of digitized data are useful compared to paper based data in the sense of the flexibility of the data. Loan services, (for example, Library, Rental video, debt etc., ) are among the services that makes use of sophisticated digitized transactions. Loan services handle a lot of personal information, which enables the analysis of personal hobby and tastes, or even life style. Hence, administrators who control the loan information are able to obtain personal information of customers, which leads to a large privacy problem. We have examined a way to avoid this privacy problem. One solution is to use “An Anonymous Loan” that the user can be anonymous while borrowing and returning, but the anonymity is unveiled only after the due date without return. We will suggest An Anonymous Loan System using tamper resistance device and Group Signature Scheme.