Guest teachers were family tutors in the Song Dynasty. On the one hand, guest teachers were poor and depended on their host families. Besides educational activities, they also participated in the cultural entertainment and social activities of the host families. On the other hand, scholars regarded guest teaching as a transitional profession; thus, they were a mobile group. The interpersonal communication of guest teachers was centered on the host families. They promoted the development of education for common people in the Song Dynasty, contributed to the spread of Confucian culture, and set an example for local moral education with their scholarly moral standards. Hong Mai's Yi Jian Zhi contains many records about guest teachers in the Song Dynasty, providing vivid materials for us to understand the group of guest teachers in the Song Dynasty in detail.