Abstract: In recent years, Japan has attached great importance to the defense exchange and cooperation with India, constantly constructed the dialogue mechanism including overrall security, defense policies and military affairs, and intensified the military cooperation and exchange in the form of joint military exercises and joint training, with the result that the exchange at various levels of military and security departments has greatly been strengthened and that the quality and level of the strategic cooperation have been increasingly improved. By means of these measures, Japan is intended to ally with India to hamper and keep guard against China, so as to ensure the security of Japan's sea routes and to create a good condition for Japanese Maritime Self Defence Force to go to the ocean and intervene in problems about the South China Sea.