The Laboratory of Autoimmunity from Medical College has been dedicated to studies of autoimmune diseases ever since its establishment in 2011. In this paper, the research group led by Dr. Zheng Junfeng has found that in HLA-II, HLA-DRB1*0803 is the susceptibility gene of primary Sjogren’s syndrome in southern China. Structural bioinformatics modeling and analysis of molecular structure of DRB1*0803 further demonstrates that the variations of the electrostatics of peptide binding pocket 9 may be the molecular foundation of variations of diseases susceptibility. Autoimmune diseases are jointly caused by heredity and surroundings; in heredity, HLA loci are the main susceptibility genes for most autoimmune diseases. Though it is clear that HLA and autoimmune diseases are closely connected, the mechanism of the connection remains unknown. This research of the connection between HLA and Sjogren’s syndrome presents pioneering discoveries and put forward brand-new points for that mechanism. This paper comes as the forth of a series of published papers on Sjogren’s syndrome by the Laboratory of Autoimmunity.