Environmental governance is widely discussed by studies on government policy-making. Its importance is also stressed by numerous international environment conventions. In recent years, environmental governance also become a hotspot of international investment law studies. In particular, greenhouse gas emission is one of the most attentive subject to environmental governance studies. Governments set various regulations to ease off the worsening condition of global warming according to international environment conventions. International treaty other than environmental ones might still have an effect on environmental governance. With studies proving the positive relation between greenhouse gas emission and investors, it seems interesting to clarify the correlation between BIT and environmental governance. We conduct a series of statistical test on greenhouse gas emission and BIT. Greenhouse gas emission is taken as dependent variable, and treaty obligation of BIT is taken as independent variable. The following literature provides a proof that complying with higher BIT obligation could result in higher greenhouse gas emission. However, government’s will on environmental protection which is taken as a moderator in our models could ease the worsening environmental governance. In order to gain economic benefit, treaty parties comply with BIT obligation. Complying with BIT is proved by numerous studies to enhance the regulatory quality in a state, but it also means partial restriction of state regulatory right. Especially in the realm of environmental protection, “centering effect” constraints state environmental regulatory right in a certain condition. If states stress on the importance of the balance between environmental protection and investor protection, it’s possible to diminish the impact on environment which is brought by BIT.