In this paper, first, the concept of the most significant relationship principle and relevant indicating the full points and the most significant relationship principle established process; Secondly with typical cases put forward the principle most closely the emergence and development; Once again the most significant relationship principle expounded the specific application, especially focusing on the use of foreign contract areas; Finally, from the legislation of the guidelines and puts forward the specific terms legislation in our country the principle of private international law in China's legislative situation, and the status of judiciary. Meanwhile, in the analysis of domestic and foreign applicable conditions, serious consideration this principle, proposes the effective countermeasure, favors to better use. Based on balance and protecting the interests of the most closely contact, promote the principles system and in-depth explore for purpose, through the analysis of the present situation and the most significant relationship principle of thorough research will help the development of private international law country, thus can very good protection of foreign contract relationship party's legitimate interests, promote international civil association international economic relations the smooth development, also be helpful for one country economy development and the rejuvenation of the ethnicities. The most significant relationship principle itself is flexible and open, this makes it can along with the development of society, to achieve continuous self-improvement substantial justice in providing the most powerful safeguard, foreign-related contracts to exert its function field.