Abstract: The green principle is a new civil law principle, and its judicial application has attracted much attention. As the principle of right law, the green principle lies between the idea of natural law and the rule of law, and has both the idea of natural law and the shell of positive law. As a result, the judicial application of the green principle is complicated, which includes three types of application: the trade-offs application of principle, the hermeneutic application of principle to rule and the subsumption application of principle as rule. For trade-off application, the green principle determines whether it is applicable or not and the proportion of application by balancing its weight with the conflicting principle. For hermeneutic application, the green principle influences the interpretation of legal rules with green value by intervening in the process of the subsumption of legal rules. For subsumption application, the green principle is regarded as a rule to fill the legal loophole and complete the application through the civil law system to compensate for its legal consequences. The green principle, as the condensation of the green consensus reached in the value level of contemporary civil society, closely connects the green value concept with legal rules, and realizes the updating and iteration of civil law doctrine towards green with the help of the judicial application of the green principle.