Routine blood test alone is not able to diagnose dry syndrome. Dry syndrome is a common autoimmune disease. Clinically, the diagnosis of dry syndrome should firstly be based on clinical manifestations such as dry mouth, dry eyes, dry skin, fatigue and weakness. Secondly, it is also necessary to refer to immunology related examination, the most important of which is autoantibody examination, such as anti-SSA antibody and anti-SSB antibody, which are specific antibodies for the diagnosis of dry syndrome. Anti-nuclear antibody, immunoglobulin G, complement C3 and complement C4 levels can also be used as reference standards for the diagnosis of dry syndrome. And the routine blood test can only indicate the number of white blood cells, red blood cells, platelets and hemoglobin in the blood, excluding the above autoantibody items.