In today’s international relations, there are not only economic and political games but also rule games. To strengthen the protection of domestic investors and attract foreign investment, many countries attach more importance to the negotiation and conclusion of international investment treaties. The negotiation of international investment treaties is greatly influenced by the subjects of international law, national policies and international relations. As one of the sources of international law, international investment treaties are also branded with the characteristics of limited rationality of international law, behavioral international law reveals the existence of limited rationality, it can play a guiding role in the drafting and development of international investment treaties. When negotiating international investment treaties, China should guard against its weaknesses, avoid being blinded by limited rationality, conclude rules of international law consistent with historical conditions, and maximize the effectiveness of international investment treaties.