Since the internet is a widely used tool in many business areas these days, a large amount of contents are offered through the web. Almost all of them, however, are being provided to users without any protection. Anyone can copy and reuse the contents without permission by using features of the web browser and even use them for commercial purposes. It is time to consider having countermeasures to protect the web contents from illegal use and leakage. Therefore, this paper proposes security requirement of web contents protection system by modeling a threat and applying a security requirements engineering methodology base on common criteria v3.1.