This research mainly focuses on the group theory model Contents of Mainland China's Decision-making Model in Taiwan Affairs At the same time, the influence of interest groups under the theoretical framework is discussed Using youth groups as data in this study to support relevant research findings At the same time, the mainland's Taiwan work has changed with the process of reform and opening-up in mainland China Under the new administrative system, what form will the mainland's work in Taiwan take in the future is also the research objective of this paper It is hoped that this study will outline the framework of mainland China's work on Taiwan affairs Find out the changes in Taiwan affairs in the mainland from the past to the present It helps to understand the core of its transformation.