Crowdfunding is a compound word of "crowd" and "funding", meaning a practice where those in need of money raise small-scale funds from the general public via intermediaries mostly over the internet. In general, crowdfunding is classified into four types according to the purpose of funding activities and consequent benefits in return: donation-based, reward-based, lending-based, and securities-based crowdfunding. The CROWDFUND Act, included in the JOBS Act Title III on 5 April 2012, is the law establishing the rules applicable to securities-based crowdfunding in the U.S., and it mandated the Securities Exchange Commission ("SEC") to prepare for the implementing rules for the CROWDFUND Act. On 30 October 2015, at last, SEC adopted the long-waited implementing rules for the CROWDFUND Act, Regulation Crowdfunding. Meanwhile, Korea also set up its securities-based crowdfunding regime by amending to the Financial Investment Services and Capital Markets Act ("FSCMA"). The Korean crowdfunding regulation embedded in the FSCMA has been prepared modeling after the CROWDFUND Act. Therefore, both Korean and U.S. crowdfunding regulations share many common features. In some important, specific areas, however, it seems that some deficiencies are found in the Korean regime compared to the U.S.``s. In this regard, this article tries to overview some crucial aspects of Regulation Crowdfunding from the perspectives of issuers, investors and intermediaries in Regulation Crowdfunding. After exploring Regulation Crowdfunding and finding several regulatory gaps between the Korean and U.S. regulations, this article concludes with comments which may rectify the gaps.