In this paper, we will propose a novel fair transaction protocol based on electronic cash. With the extension of untraceable electronic cash, we have designed a fair transaction protocol to satisfy both the anonymity and the fairness properties simultaneously. Under the existence of an off-line trusted third party (TTP), the protocol is efficient and practical. Furthermore, the payment information of each customer is not revealed to anyone else including the TTP, and thus, the anonymity or privacy of the customer is protected completely in our protocol. Especially, the proposed method is independent of the underlying electronic cash (e-cash) scheme such that it can be realized by any e-cash system based on the concept of blind signatures.