The core of think tanks public diplomacy lies in the twoway communication and public opinion communicationIts functions are to influence public opinion, to increase the national ideology power in international public opinion arena, to enhance understanding and mutual trust, and to put forward policy advice to promote government diplomacyThe mechanism for think tanks public diplomacy to exert influence is the transformation of thoughts to power, by the diffusion of ideological power and its core position to influence public opinion in public policy opinion filedThe communication model of think tanks public diplomacy falls into two parts, which is twoway symmetric communication model and think tankdominated convergence communicationFor Chinese think tanks public diplomacy to achieve excellent effects， it requires the comprehensive development of a new type of think tank with Chinese characteristics, enhancing creativity in think tanks thoughts with the talent as the core, increasing communication effects of think tanks public diplomacy in practices by deepening the theory