Abstract: The rise of emerging multilateral development banks,has challenged the Japan-U.S.dominated Asian development finance system.To maintain national interests, Japan has sought to reshape the regional development intervention regime of Asian Development Bank, which is concretely manifested in, the ideologizing of economic concepts, and the emphasis on Quality Infrastructure Investment to strengthen competitiveness. Japan also adopted a “selective intervention” approach under the Regional Cooperation and Integration(RCI)framework: maintaining deep intervention in the GMS, offering targeted assistance to a specific country in the SASEC, and making CAREC into a “new battleground” for critical minerals.These reshaping ways had weakened the Asian Development Bank's role as a provider of public goods, while making it into geopolitical instruments in certain areas, which aim to serve Japan's regional economic diplomacy strategy.Meanwhile, identity fragmentation put Asian Development Bank into an efficiency paradox and exposed the risk of marginalization.To avoid the risk, Asian Development Bank must shift away from a confrontational mind and promote cooperation among development financial institutions.

Key words: Asian Development Bank(ADB), Japan, Multilateral Development Banks(MDBs), Quality Infrastructure Investment, Regional Cooperation and Integration(RCI)