Primary antibody deficiencies (PADs) are the most common inherited primary immunodeficiencies in humans, characterized by hypogammaglobulinemia, an inability to produce specific antibodies, and recurrent infections mainly caused by encapsulated bacteria. However, it has been shown that inflammatory disorders, granulomatous lesions, lymphoproliferative diseases, cancer, and autoimmunity are associated with the various types of PAD. Both systemic and organ-specific autoimmune diseases could be attributed to B-cell defects in PAD patients. Immune thrombocytopenic purpura and autoimmune hemolytic anemia are the most common autoimmune disorders in this group of patients. The aim of this review is to describe the proposed mechanisms for autoimmunity and to review the literature with respect to the reported autoimmune disorders in each type of PAD.