Due to underlying autoimmune background of Guillain-Barré syndrome (GBS), the possible role of infectious agents cytomegalovirus (CMV) and Epstein-Barr virus (EBV) and also due to association of anti-ganglioside antibodies with GBS, the present study aimed to investigate the associations between serum anti-ganglioside antibodies (AGA) level, type of infection and electrodiagnostic (ED) findings with the severity and three-month functional outcome of patients with GBS. Here, AGA is linked to infection.