In order to overcome the shortcomings of the basic principles established by the Environmental Protection Law (as amended in 2014) (EPL), and to reflect the new characteristics of the Eco-environmental Code, the basic principle system of environmental law should be further developed and improved. In compiling the Eco-environmental Code, the basic principles set forth in Article 5 of the EPL should first be selected based on the standards of legality and fundamentality. These principles must then be reinterpreted to clarify their legal meanings, and new basic principles should be introduced to meet the requirement of systematization. According to these requirements, the basic clauses in the proposed Eco-environmental Code should exclude the principle of comprehensive management and the principle of liability for damage, while incorporating the principle of equitable distribution of environmental interests, the precautionary principle, the non-regression principle, and the principle of burden on environmental actors. This approach constructs a system of mutual cooperation and restraint, with sustainable development as its internal logic. The system will encompass the principles of protection priority, risk prevention, prevention as the primary strategy, public participation, prohibition of regression, fair distribution of environmental benefits, and allocation of environmental responsibility. In terms of specific legal expression, the Code should adopt separate, independent norms to articulate these basic principles through complete clauses, thereby to ensure the auxiliary function of these principles in judicial adjudication.