The purpose of this paper is to analyze for Abe Administration`s Right-wing policies and Strengthening the U.S.-Japan Alliance to impact on the Northeast Asian regional security situation. Launched in December 2012, Abe`s 2nd term Government domestically has been promoting Right-wing policies, such as visiting Yasukuni shrine, reviewing Kono Statement. And also Abe government is trying to exercise the right of collective self-defense, amended ‘the US-Japan Defense Cooperation Guidelines’ and to pursue a missile defense system for strengthening the U.S.-Japan Alliance. Abe Administration`s Right-wing trend and Strengthening the U.S.-Japan Alliance eventually provoke conflicts between the US-China in the Northeast Asia, strengthen the cooperation between China and Russia, and deteriorate between China and Japan and the Korea-Japan relations, and exert negative impact on the ROK-US Alliance and the Korea-U.S.-Japan security cooperation. Therefore, the Republic of Korea is necessary to make wise judgment politically after carefully analyzing the change of the mutual relationship with Korea`s neighbors. First, Korea should avoid switching to a hostile relationship with the other party as selecting one between the US and China. And, for establishing a new future-oriented Korea-Japan relationship, it is necessary to refrain from emotional response, and then to promote pragmatic diplomacy such as actively pursuing common denominators of national interests. And it also needs to maintain an organic relationship of Korea-US-Japan through strengthening Korea-US alliance while controlling Japan.