Now, relationship between great states appears to have the following features: Four great states in Asia-Pacific region develop their bilateral relationship in the progress of restrict condition each other; economic cooperation and competition in peace becomes the vital element in developing.

Cultural diplomacy is an effective approach of diplomacy, which plays a role of promoting mutual understanding and trust among nations and peoples, constructing and improving the international prestige and soft power of a state.

The present paper,based on the speech act theory and conversation analysis,attempts to investigate the relationship between speech acts and mutual understanding from the illocutionary logic of the sequential structures in conversation.