Abstract: By borrowing the two-stage theory from Germany to construct green certificates in a two-stage manner, the full life cycle management of green certificates can be divided into two distinct legal relationships. The first stage, which involves the establishment of files and issuance, has the public law attributes of administrative licensing and administrative confirmation. The second stage, which involves the trading and write-off of green certificates, is characterized by private law adjustment and the integration of public power. The time point for the two-stage division lies in the completion of the green certificate issuance. The two-stage structure of green certificates has its unique features, mainly reflected in the intervention of public power in the second stage. This is mainly manifested in the following aspects: on the one hand, there is a large amount of public power intervention in the rule formulation and market supervision of the green certificate trading stage; on the other hand, the green certificate write-off stage integrates the act of government confirmation, thereby modifying the second stage of the two-stage structure of green certificates to the model of "civil contract administrative act". By analyzing the legitimacy, legality and intervention limit of public power in the green certificate market, relevant improvement suggestions are put forward.