Dry syndrome (Sjogren’s syndmme, ss) is a chronic inflammatory autoimmune disease that predominantly affects the exocrine glands and may be associated with other systemic involvement. The pathology is characterized by inflammatory infiltration of large numbers of lymphocytes in the exocrine glands throughout the body, resulting in glandular destruction, ductal stenosis and obstruction, and ultimately a decrease and lack of glandular secretion. Dryness of the mouth and eyes is a common symptom, often accompanied by visceral damage and a variety of clinical manifestations. This disease is divided into two categories: primary and secondary. Those who do not combine with other autoimmune diseases are called primary dry syndrome; those secondary to rheumatoid arthritis (RA), systemic lupus erythematosus (sLE), systemic sclerosis (SSC), etc. are called secondary dry syndrome. Yu dry syndrome is more frequent in women, especially in postmenopausal women, and the age of onset is concentrated in 30 to 60 years old. Epidemiological survey shows that the prevalence of the disease in China is O.3%-0.7% (varies with different diagnostic criteria), and the prevalence in the elderly population is 3%-4%, and its prevalence is significantly higher than that of SLE and similar to that of rheumatoid arthritis (0.36%), and is currently considered one of the most common connective tissue diseases.