In glaucoma, the elevated intraocular pressure cannot explain the disease in all patients. However, the pathogenesis of the disease is widely unknown. Autoimmune effects could play a role in the disease process. Several studies using Western blotting, mass spectrometry and microarrays could demonstrate significant and persistent up – and downregulations of immunoreactivities against ocular antigens. Furthermore, in animal models it could be shown that in priniciple the immune reaction itself is able to lead to retinal ganglion cell loss. A deposit of antibodies could be shown in the retinae of glaucoma patients. These findings could lead to a better understanding of the pathogenesis, but also to new immunomodulatory treatment options and diagnosis.