Recently, it is becoming widespread practice for international investment treaties to preserve the right of regulation. The right is an expression of a country’s sovereignty in international investment field. This is the general right of state to regulate foreign investment, and to restrict the right is exception. The purpose of regulatory right expressed in recent investment treaties by North/South countries is somewhat different. Their common aim is to correct an unhealthy situation in international economic order, without an intention of retreat into investment protectionism. For their common aim, the preservation of the right to regulate by new investment treaties still follows two principles concerning international investment market regime, and this will further the development of a sustainable liberal international investment market regime.