China's climate governance is distinguished by the contrast between an abundance of policies on climate change and the lack of legally binding laws. This article argues that Chinese courts bridge this difference, which fosters a ‘rule of climate policy’ rather than a strict rule of law. The effective authority of Chinese climate policy is made possible in practice both by provisions of the Chinese Constitution and the prevailing use of legal reasoning. China's constitutional design of ‘ecological civilization’ delegates the duty and the power of managing climate change issues to the executive branch of its government. Most Chinese documents on climate governance have no binding legal force, which means, according to positive law, that they cannot serve as legal grounds for judicial decisions. Chinese judges, in deciding climate-related disputes, must combine legal provisions and non-binding materials to achieve regulatory goals. They use non-legal materials to support statutory or contractual interpretations and determine the existence or limits of rights, which alters the meaning and scope of existing legal terms and principles. This rule of climate policy is possible in the courtroom because judges justify public policy considerations with arguments of principle that are substantiated in various non-binding climate plans.