Guillain-Barré syndrome (GBS), an acute immune-mediated neuropathy, occurs following immunological stimulation, such as infection, with complement-mediated neuropathy implicated in the pathophysiology of this condition. Glycolipid antibodies produced by molecular mimicry are detected in approximately 60% of cases. Recent studies have suggested the role of cell-mediated immunity in the pathogenesis of GBS. Intravenous immunoglobulin and plasma exchange are established immunotherapies. In this article, based on the latest knowledge, we describe the pathophysiology, diagnosis, treatment, prognosis, and prognostic prediction of GBS. Furthermore, we discuss some GBS guidelines published by the European Academy of Neurology/Peripheral Nerve Society.