As a domain name can be registered simply by filing an application for registration, disputes over the domain name between the holder of domain name and the holder of trademark increased. Since the holder of trademark who was late for registering domain name is willing to pay for the return of domain name, cybersquatters increased. Cybersqatters are not genuine users of the Internet. This article is to compare the construction of law by American Courts and by Korean Courts and to assert the creation of the law similar to the law of US as to anti-cybersqatting. American Courts applied the Trademark Act and the Anti-Dilution Act to resolve the disputes over domain name. To apply the Trademark Act, the Court required the plaintiffs to prove that the goods or the services expressed by the domain name should be identical or similar to the goods or the services represented by the trademark. However, there were many cases where the holder of domain name used it for the goods or the services irrelevant to those of the holder of trademark. Also, the Anti-Dilution Act could not successfully protect the holder of trademark from cybersquatters because it required that the trademark should be famous or distinctive. As a result, the US promulgated a new law which is designed to prohibit cybersquatters from being free of sanction by the existing laws. Korea Courts applied the Trademark Act and the Unfair Competition Prohibition Act to the cases disputing domain name. Likewise in the US, Korean Courts must cope with the issue of identity of the goods or the services, and the famousness or distinctiveness of trademark. The Courts hesitate to give a winning judgement to the holder of trademark simply because the domain name of alleged violator confused the trademark. Some scholars advocate the broadening of construction of the Unfair Competition Prohibition Act to illegalize cybersquatting but it is beyond the meaning of the law. Accordingly, it is a time to make a law similar to the Anti-Cybersquatting Act of the US. The law must be a fair and reasonable compromise to resolve the collision between system of registration of domain name and the system of registration of trademark. Some commentators advocate that the registration of domain name should be examined just as the one of trademark and to facilitate it, the Patent and Trademark Office should have jurisdiction of registration of domain name. But it abandons the distinction of domain name and trademark and results in obstructing e-commerce. By adopting the Anti-Cybersqatting Act, we can prohibit it. In other cases, we get a reasonable adjustment between the holder of domain name and the holder of trademark through the Trademark Act and the Unfair Competition Prohibition Act.