However, the relationship between B7-H4 and autoimmune thyroid diseases (AITDs) has not been explored.<h4>Objective</h4>To investigate the B7-H4 expression in different tissues of patients with different subtypes of AITDs.<h4>Methods</h4>The B7-H4 protein expression in thyroid tissue of the participants was identified through immunohistochemical analyses while concentrations of plasma soluble B7-H4 (sB7-H4) were detected by enzyme-linked immunosorbent assay (ELISA). Here, VTCN1 is linked to autoimmune thyroid disease.