Zhang Huaiguan was an outstanding calligrapher and theorist in the prosperous Tang Dynasty. Kaiyuan years, because of the title of the book was recruited as a sacrificial Hanlin. He first received an official and part-time salary in Youfu, and then received the salary of Sima Shengchuan, but he didn't actually take office. In the first year of Gan, it was interpreted as Ezhou Sima. Zhang Huaiguan entered the official ranks from the eighth grade, and finally from the fifth grade. Zhang Huaiguan's father, Zhang Shaozong, is good at calligraphy. In Shu Duan, I talked about my father's calligraphy: learn high first, then learn Chu Suiliang's brushwork, and then change my mind. Zhang Shaozong's last official position was Shaozhou Wugang county magistrate. In the Theory of Six-body Calligraphy, Zhang Huaiguan also mentioned that his brothers Zhang Huaixuan and Zhang Huaixuan were also good at calligraphy: "My brother and I are in love and dedicated to each other. I would like to enter the book with eight points of Xiao Zhuan, the book is true, and the cursive script is combined into six bodies. " Zhang Huaiguan was born in an official's family, and he was good at the truth, line, cursive script, seal script and eight-part essay in calligraphy. In Liu Ti Shu Lun, he argued that truth and deeds "can be compared with Yu (Shinan) and Chu (Sui Liang)", and cursive writing "only took hundreds of years". Zhang Huaiguan left behind a rich and complicated book history and monograph. Only Shu Duan, Guan Shu, Yi Shu, Wen Zi, Liu Ti Shu Lun, Ten Techniques of Using Pen, Forbidden Sutra in Yutang, Calligraphy Review and Medicine Stone have been handed down from generation to generation. There is also a volume "The Ancestor of Ancient Seal Characters in China" and an article "Book Fu", which unfortunately has not been passed down. Zhang Huaiguan's monographs have a profound understanding and detailed exposition of the origin and development of calligraphy, its essence, its position in social life, learning methods, calligraphy technique theory, calligraphy appreciation and calligraphy criticism. His book theory works covered all aspects of China and calligraphy theory, and constructed the basic framework of calligraphy theory in ancient China. Hope to adopt, thank you.