In Korea, confirming the identity of persons or adult identity verification on a visiting website or E-commerce activity on the internet is processed by asking users to become registered on it. There are several tools to confirm the identity of an individual on the internet such as Resident registration number, i-Pin, Public Verification Certificate, Cell phone certificate and Credit card certificate etc. Among them, Resident registration number is mostly common used and bound to be easily drained or stolen while in the process of storage or forwarding due to the internet characteristic of open-end network. Indeed, it happens often that draining or stealing of Resident registration number on the internet since it has been commercialized. By the way, Resident registration number includes important and sensitive personal information such as date of birth, gender and place of birth. Also, Resident registration number could be used as a medium of collecting personal information very easily. Thus, draining or misusing of Resident registration number may cause invasion of privacy and mental as well as economic damages against individuals. More serious effect is expected due to the limitation and weakness of Korean Resident registration number that is impossible to be discarded or changed when it’s drained or stolen. Because the confirming the identity on the internet is processed with correspondence of Resident registration number and name, there are many cases of steal and misuse of other’s Resident registration number in Korea. In this situation confirming the identity by Resident registration number is not effective and need reformation. In other major countries different from in Korea, individual can be a registered user and use the service without confirmation process using personal identification number for the E-commerce or entertainment website. People just need to enter their name and e-mail address, and basic payment information when it’s charging service. For instance, name and e-mail address are only necessary when someone wants to be a registered user of international internet shopping mall like eBay or Amazon. Thus, to prevent damages and diminish any harm from stealing or misuse of Resident registration number, we need to consider limit and prohibit confirmation of the identity with Resident registration number. Internet service providers should use other tools when it is necessary to confirm the identity of an individual for operating their services. Confirming the identity using Resident registration number should be permitted only when it’s regulated under the law. In addition, it is desirable to revise the law in order to promote use of other tools of confirming the identity of individual and regulate minimum inevitable use of the Resident registration number.