For hostile takeovers, there is a model of regulations that focus on acquisition behavior, as well as a model of regulations that focus on the hostile takeover defensive of the target company. while Japan, have not only made corresponding provisions for the acquisition, but also allowed the target company to implement the model of hostile takeover defensive under certain circumstances. This draft summarizes the hostile takeover defensive that can be adopted under the Japanese Public justice system and the duties and liabilities of the directors of the target company in the hostile acquisition.