Abstract:In the process of advancing the modernization of the national governance system and governance capacity, the important role of think tanks becomes increasingly prominent. Because of the comprehensive crossover characteristics of think tank research problem, it manifested as different scale research problems. The research process follows the general and common methods of the think-tank DataInformation-Intelligence-Solution (DⅡS) theory, and has different key elements and steps. Grasping these key elements and steps and forming different scale DⅡS methods can provide effective tools and methods for individuals, research groups and research teams to investigate the think tank research problems. From the perspective of crossing, relevance, and complexity, this study analyzes the characteristics of largescale, medium-scale, and small-scale think tank problems, and develops the process of dividing the scale of think tank problems. Secondly, large-scale, medium-scale, and small-scale think tank DⅡS methods are proposed based on the DⅡS theory, and the relationships of them are investigated. Finally, the DⅡS writing specifications of think tanks of different scales are developed in order to ensure the normative and high quality of think tank research and to better play the role of think tank.