The study objectives of this research work is to survey the China's diplomacy in the evolution of trilateral relations between China, the U.S. and Russia (the Soviet Union). The research methodology is based on a complex combination of scientific methods in a chronological order, mainly analytical, empirical, systematic, comparative, situational, narrative, and descriptive. The scientific novelty of this article is to provide the general observation of the key period of the historical evolution process of the existing strategic triangle in a large-scale timeline, meanwhile reveal the significant connection between domestic politics of single factor and trilateral relations within this triangle. The obtained conclusions can be applied in managing more stable and positive trilateral relations in complexity of international relations and comtemporary global politics, by defining the features of the modern strategic triangle and each countries' role inside, indicating rising China's new role and foreign policy direction in a new era.