In the last two decades, modern international investment law has been attacked a lot for its tow source including investment treaties and judicial procedure arising from treaties. Attacks that have sometimes challenged the nature of the International Investment Law regime. At the same time, from the last decade until now, due to the growing correlation between trade and investment in 21st century and the need for correlational regulations, the trend towards concluding "mega-regional trade agreements" in order to establish an integrated system of international trade and investment regulations has increased significantly. The present study, while briefly examining the fundamentals of governments' tendency to create macro-examples of regional trade agreements as well as the challenges that these agreements will face in achieving this correlation in the field of investment regulation, by analyzing the provisions of the macro agreements, it outlines the potential implications of these agreements in order to solving challenges in the field of international investment law. The present study believes that regional mega-regional trade agreements are not only able to address the challenges posed by providing balanced examples of investment treaties, rather, the creation of these agreements with balanced regulations and macro-structural features can provide the context for a stabilizing transformation in the various resources of the international investment law regime.