Many electronic payment mediums have been introduced with remarkable developments in Information and Telecommunication technologies. The use of electronic money as one of the electronic payment mediums has been astronomically increased due to its advantages in storage of value, ability to be recharged, usage in various areas, and ability to complete the transaction immediately. However, the financial transactions based on electronic money inhibit several legal problems as the existing legal system does not state on this form of transaction. This research is, therefore, to discuss the possible legal methods to regulate the problems that may arise from using electronic money. The summary of the research is as follows. First, electronic money is a payment medium which differs with credit cards, gift certificates, or electronic transfers in that it is stored with the monetary value in electronic medium such as computer, IC card, and network, and then, utilized in transaction of goods and services. Secondly, in consideration of the monetary function of electronic money as storage of value and payment medium, an issuer of electronic money should be a financial institution with public authority, which is stable and financially transparent and has attained credibility in its operation to manage and operate electronic money. In case of non-financial institution, it is proper that the issuance of electronic money is authorized under the condition that it collaborates with a financial institution. Thirdly, an issuance contract of electronic money shall be deemed as a transaction contract which offers the user with the complete right to be refunded. Fourthly, although the payment with electronic money contains similarity with the performance of obligation in light of compensating the seller of goods and services, it is appropriate to regard it as one of the substantial/onerous contracts, that is an exchange of goods, since the user has the obligation to the substitution right of seller in repayment and on collateral. Fifthly, the loss that has occurred in using the electronic money shall be shared by the issuer and the user, considering the obligation of issuer in providing credibility and stability.