Abstract: Carbon-emission trading is a major practical and theoretical issue in China. Its policy development has gone through three stages:theoretical exploration,local pilot operation and national market construction. In the development process of carbon-emission trading policy,the government,trading platforms,trading subjects,experts and scholars are undoubtedly the key elements in promoting policy development. Each of the four types of actors has its own role and strategic behavior in the process of carbon-emission trading policy. At the same time,the four types of subjects are not isolated passive individuals,they rely on each other and influence each other. This dynamic interactive process forms the relationship structure between subjects. In order to effectively ensure the positive interaction between the four types of subjects and constantly optimize their structural functions,it is necessary to make full use of the role of market mechanisms,synergize the dynamic power of subjects,and improve the legal guarantee system by layers,thus promoting the healthy development of China's carbon-emission trading policy and carbon market.

Key words: carbon-emission trading policy, subjects, inter-subject relationships, dynamic roles