The diary of prime ministers of Song dynasty possesses fundamental academic and cultural value. During the northern song and southern song dynasty, direct conversation strategies used in the diary started transforming to a orthodox article where writers' true emotion was gradually concealed. At the same tine, the original narrative style with overall degree was replaced by logical illustration with specific opinions; it began to evaluate receivers' capacity of psychological acceptance to the strategies and suggestions brought forward. Therefore, the former pace of narration was eternally disturbed. As a matter of fact, the mental transmission from "Serve the king" to "Serve both the king and other ministers" reveals the decrease in prime ministers' political power. In addition, the focus of their strategies and suggestions changed from provoking king's empathy through logic statement to engendering king's sympathy by means of petition and confession. Making use of diaries, prime ministers in Song dynasty put on their persona, behind which was the prevailing exhaustion both physically and mentally. Narrative method such as disappearance of subjects, identity switch and Writing in detail came to emerge at the very moment.