As a part of the national diplomacy，public diplomacy is an important way to enhance the national image and smart power through the international communication and intercultural exchange. This paper focused on the diplomatic practice of president Xi Jinping’s state visit to Britain in 2015，in order to analyze the characteristics and strategies used in public diplomacy：mutual respect in trans-cultural dialogues，various diplomatic forms about the bar culture and football，mutual complementary relations between the elite and ordinary people. Under the background of global economic integration，this paper also analyzes the ways to improve national image from the view of government，the public，media and culture.