Three Sus are the leaders for the studies on Shu Science in Song Dynasty, and Su Xun, as the parent of Su Shi and Su Zhe, played an important role in the formation of Shu Science at early of Shu study. The ancestors examined three Sus, mainly focused on Su Shi, neglected Su Xun and Su Zhe. As an un-neglecting official in North Song Dynasty for worrying and happy for the people, the literature creations of Su Xun had deep era atmosphere, especially his history studies which upheld "meaning first and then style", which carried out the pursuit of moral governance and political governance in his historic theses and which became the bellwether affecting historic thesis creations of Su Shi and Su Zhe. The studies on the literature color of Song Dynasty of Su Xun theses can provide very precious experience for comprehensively understanding of the thoughts of Three Sus on Shu Science and for the development of the researches on the historic theses in two Song Dynasties.